abortifacient: Induces abortion or miscarriage.
abscess: A localized collection of pus and liquefied tissue in a cavity.
absolute: A highly concentrated viscous, semisolid, or solid perfume material, usually obtained by alcohol extraction from the concrete.
acetylcholine: A neurotransmitter. Its effects include cardiac inhibition and increase in blood vessel diameter.
achlorhydria: Absence of hydrochloric acid in the stomach.
acid: A compound producing hydrogen ions in aqueous solution. Acidic refers to a pH below 7.0.
acidosis: Abnormal state of reduced alkalinity of blood and tissues.
acrid: Leaving a burning sensation in the mouth.
ACTH: See adrenocorticotropic hormone.
acute: Designating disease with rapid onset, severe symptoms, and brief duration; opposite of chronic.
acute abdomen: Emergency condition caused by damage to one or more abdominal organs that results in intense pain and shock.
adaptogen: An herb that increases resistance and resilience to stress, enabling the body to avoid reaching collapse because it can adapt around the problem.
adenoma: An ordinarily benign (nonmalignant) tumor of skin tissue.
Addison’s disease: Condition marked by weakness, low blood pressure, and dark pigmentation due to inadequate hormone secretion by adrenal glands.
adenitis: Regional inflammation of gland or lymph node.
adenocarcinoma: Malignant epithelial tumor in glandular pattern.
ADH: See antidiuretic hormone.
adhesion: Union by fibrous connective tissue of two normally separate parts.
adipose: Fat in connective tissue.
adjuvant: Any substance that enhances the immune-stimulating properties of an antigen or the pharmacological effect of a drug.
adjuvant chemotherapy: One or more anticancer drugs used in combination with surgery or radiation therapy as part of the treatment of cancer. Adjuvant usually means “in addition to” initial treatment.
administration: This term refers to how a drug is taken.
adrenaline: Hormone secreted by the adrenal gland, which produces the “fight-or-flight” response. Also called epinephrine.
adrenergic: Compound that acts like epinephrine or norepinephrine.
adrenocorticotropic hormone (ACTH): Polypeptide secreted by anterior pituitary that stimulates the adrenal cortex to secrete cortisol.
adverse drug reaction (ADR): Defined by the WHO as “any response to a drug which is noxious and unintended, and which occurs at doses used in man for prophylaxis, diagnosis, or therapy.”
aerophagy: Swallowing of air.
aflatoxin: A toxic chemical produced by the Aspergillus flavus and A. parasiticus molds.
agar: Polysaccharide derived from seaweed, used as culture medium for microorganisms; gelatinous natural laxative.
agglutinin: Substance, especially antibody, that causes bacteria, blood cells, and antigens to clump.
agonist: A drug that both binds to receptors and has an intrinsic effect.
agranulocytosis: Acute illness caused by chemicals or drug reaction in which certain white blood cells disappear, causing rapid, massive infection.
ague: Malaria; general malaise marked by fever.
AIDS: Acquired immune deficiency syndrome; severe weakening or destruction of body’s immune system by human immunodeficiency virus.
AIDS-related complex arc: Chronic enlargement of lymph nodes and persistent fever caused by AIDS virus.
albumin: Most abundant protein found in blood plasma.
albuminuria: Presence of the protein albumin in urine. aldosterone: A hormone secreted by the zona glomerulosa of the adrenal gland, which causes the retention of sodium and the secretion of potassium.
alga: Unicellular organism distinguished from plants by having no true root stem.
alkaline phosphatase: A blood enzyme measurement that indicates the health of the liver.
alkaline: Solution having a pH above 7.0.
alkaloids: A large, varied group of nitrogen-containing compounds found in plants. Often alkaline, they react with acids to form soluble salts, many of which are physiologically active.
alkalosis: Abnormal state of increased alkalinity of blood and tissues.
allelochemicals: Chemicals involved in interspecific communication.
allelopathy: Chemical interaction between species at all levels of complexity, from microorganisms to higher plants, inextricably interwoven into ecological phenomena.
allergen: Any substance that comes into contact with body tissue (by skin absorption, ingestion, or inhalation) and causes a specific reaction within the bloodstream.
allergy: Hypersensitivity to a particular substance or antigen, such as pollen, fur, feathers, mold, dust, drugs, dyes, cosmetics, or food, causing characteristic symptoms when encountered, ingested, or inhaled.
alliaceous: Garlic- or onionlike.
allogenic transplant: 1″I-ansfer of bone marrow from one person to another.
alopecia: Absence of hair from an area where it normally grows, especially progressive hair loss in men; baldness.
alterative: Herbs that gradually restore proper functioning of the body, increasing health and vitality. Some alteratives support natural waste elimination via the kidneys, liver, lungs, or skin. Others stimulate digestive function or are antimicrobial.
Alzheimer’s disease: Progressive dementia and brain degeneration.
amebiasis: Infection with or disease caused by an amoeba.
amebic dysentery: Severe dysentery caused by protozoan amoebas.
amenorrhea: Absence or cessation of menstruation due to a congenital defect, hormonal deficiency, hypothalamus disorder, or emotional problem.
amino acid: Any of 25 organic acids containing an amino group that link into polypeptide chains to form proteins.
amoebicidal: A substance with the power to destroy amoebas.
amphoteric: Having the ability to act as either an acid or a base.
amylase: Enzyme that breaks down starch into disaccharides.
anabolism: Constructive metabolism in which food is changed into living tissue.
analgesic: A substance that reduces the sensation of pain.
analog(analogue): A chemical compound with a structure similar to that of another but differing from it in respect to a certain component; it may have a similar or opposite action metabolically.
anaphrodisiac: Reduces sexual desire.
anaphylaxis: Acute, allergic reaction to a substance to which a person has been previously sensitized, resulting in faintness, palpitations, loss of color, difficulty in breathing, and shock.
androgen: Any substance that produces masculinization, such as testosterone.
anemia: Reduced hemoglobin in blood, causing fatigue, breathlessness, and pallor.
anesthetic: Agent that diminishes or abolishes sensation and can produce unconsciousness.
aneurysm: Balloonlike swelling of an arterial wall.
angina: Feeling of suffocation; chest pain.
angina pectoris: A suffocating pain (angina) of the chest (pectoris). Angina is a result of the oxygen demands of the heart not being met.
angiosperm: Flowering plant.
angiotensin-converting enzyme (ACE): ACE converts angiotensin I to a biologically active form, angiotensin II. ACE inhibitors are used to combat hypertension.
annual: Plant with life cycle of one year or season.
anodyne: Substance that soothes or relieves pain.
anodynia: Absence of pain.
anorexia: Loss of appetite.
anorexia nervosa: Extreme loss of appetite, especially in adolescent females, causing severe weight loss and starvation.
anoxia: Condition in which body tissues receive inadequate oxygen.
anorexiant: A drug or substance that leads to anorexia or diminished appetite; appetite suppressant.
antacid: A substance that neutralizes acid.
antagonism: The joint effect of two or more drugs such that the combined effect is less than the sum of the effects produced by each agent separately. The agonist is the agent producing the effect that is diminished by the administration of the antagonist.
antagonist: A drug that impedes the action of another chemical substance in the body.
anthelmintic: A vermifuge, destroying or expelling intestinal worms.
anther: Part of the stamen that produces and releases pollen.
anthocyanidin: A particular class of flavonoids that gives plants, fruits, and flowers colors ranging from red to blue.
anthraquinone: Glycoside compound that produces dyes and purgatives.
antianemic: An agent that combats anemia.
antiarthritic: An agent that combats arthritis.
antibacterial: A substance that stops or checks the growth of bacteria.
antibiotic: A drug that kills microorganisms.
antibody: Protein manufactured by lymphocytes that reacts with a specific antigen to fight invasion as the principal component of immunity.
anticatarrhal: Anticatarrhals help the body remove excess mucus, whether in the sinus area or in other parts of the body.
anticoagulant: Agent that prevents blood from clotting.
anticonvulsants: Helps arrest or prevent convulsions.
antidepressant: Helps alleviate depression.
antidiarrheal: Efficacious against diarrhea.
antidiuretic hormone: ADH; peptide hormone synthesized in the hypothalamus and released from the posterior pituitary, causing retention of more water in body.
antidote: A substance that counteracts the effects of a poison .
antiemetic: An agent that reduces the incidence and severity of nausea or vomiting.
antifungal: A substance that inhibits the growth or multiplication of fungi.
antigen: Any substance or microorganism that, when introduced into the body, causes the formation of antibodies against it.
antihemorrhagic: An agent that prevents or combats hemorrhage or bleeding.
antihepatotoxic: Protects liver cells from chemical damage.
antihistamine: A chemical that blocks action of histamine.
antihypertensive: Blood pressure-lowering effect.
anti-inflammatory: Soothes inflammations or reduces the inflammation of the tissue directly.
antilithic: Prevents the formation of a calculus or stone.
antimicrobial: Antimicrobials help the body destroy or resist pathogenic microorganisms. They help the body strengthen its own resistance to infective organisms and throw off the illness.
antineuralgic: Relieves or reduces nerve pain.
antioxidant: A compound that prevents free radical or oxidative damage.
antipruritic: Relieves sensation of itching or prevents its occurrence.
antiputrescent: An agent that prevents and combats decay or putrefaction.
antipyretic: Reduces fever; see also febrifuge.
antiretroviral: A substance that stops or suppresses the activity of a retrovirus such as HIV
antirheumatic: Helps prevent and relieve rheumatism.
antisclerotic: Helps prevent the hardening of tissue.
antiseborrheic: Helps control the production of sebum, the oily secretion from sweat glands.
antiseptic: Destroys and prevents the development of microbes.
antispasmodic: Substance that relieves smooth muscle spasms.
antitoxic: An antidote or treatment that counteracts the effects of poison.
antitumor: A substance that prevents or is effective against tumors.
antitussive: Substance that reduces coughing, especially one that affects activity in the brain’s cough center and depresses · respiration.
antiviral: Substance that inhibits the growth of a virus.
anxiety: An unpleasant emotional state ranging from mild unease to intense fear.
aperient: A mild laxative.
aperitif: Stimulant of the appetite.
aphonia: Loss of voice.
aphrodisiac: Increases or stimulates sexual desire.
apnea: Temporary cessation of breathing.
apoplexy: Sudden loss of consciousness, a stroke, or sudden severe hemorrhage.
appendicitis: Acute inflammation of vermiform appendix.
application: Medication, remedy, or antiseptic placed externally on body part, as in a compress.
arbovirus: RNA-containing virus that can cause disease when transmitted from animals to humans by insects.
ARC: AlDS-related complex.
aril: The husk or membrane covering the seed of a plant.
aromatherapy: The therapeutic use of essential oils.
aromatic: A substance with a strong aroma or smell.
arrhythmia: Irregularity or deviation from normal rhythm or force of heartbeat.
arteriole: Microscopic blood vessel that connects the smallest arteries with the capillary beds. Arterioles together with the smaller arteries make up the resistance vessels.
arteriosclerosis: Deposit of cholesterol on artery walls; hardening of the arteries.
artery: A blood vessel that carries oxygen-rich blood away from the heart.
arthritis: Inflammation of joints.
asbestosis: A lung disease caused by inhalation of asbestos fibers, sometimes leading to lung cancer.
asepsis: Complete absence of disease-causing bacteria, viruses, fungi, and microorganisms.
aspergillosis: A disease caused by a fungus. It can cause lesions of the skin, ear, orbit, nasal sinuses, lungs, and sometimes the bones, meninges, heart, kidneys, or spleen. Symptoms include fever, chills, difficulty breathing, and coughing up blood. If the infection reaches the brain, it may cause dementia.
assay: A test.
asthenia: See debility.
asthma: Paroxysmal attacks of bronchial spasms that cause difficulty in breathing, often hereditary; bronchial asthma.
astigmatism: Distortion of visual images due to failure of the retina to focus light.
asymptomatic: Showing no evidence of a disease.
asystole: Absence of contraction (systole). Asystole is when the heart has stopped beating.
ataxia: Shaky movements and unsteady gait when brain fails to regulate posture or direction of limb movements.
atherogenic: Having the capacity to start or accelerate the process of atherogenesis or the formation of lipid deposits in the arteries.
atheroma: Degeneration of artery walls due to fatty plaques and scar tissue; common form of arteriosclerosis, atherosclerosis. atherosclerosis: A process in which fatty substances (cholesterol and triglycerides) are deposited in the walls of medium to large arteries, eventually leading to blockage of the artery.
atony: Lessening or lack of muscular tone or tension.
atopy: A predisposition to various allergic conditions including eczema and asthma.
atrial fibrillation: Rapid irregular twitchings of the wall of an atrium (chamber) of the heart.
atrium: One of the upper chambers of the heart. Blood returning to the heart is stored in the atria before being ejected into the ventricles.
arthralgia: Severe joint pain.
atrophy: Wasting away of normally developed organ or tissue due to degeneration of cells.
attrition: Normal wearing away of surface of teeth.
autoimmune: Designating a disorder of the body’s defense mechanism in which antibodies are produced against the body’s own tissue, treating it as a foreign substance.
autoimmune disease: Disorder that permits destruction of tissue by the body’s own antibodies.
autologous: Derived from the same individual or organism.
autonomic: Occurring involuntarily, controlled by the autonomic nervous system.
axil: Upper angle between a stem and leaf.
axillary: In the armpit area.
axon: The long, filamentous part of a neuron (nerve cell) that carries nerve impulses away from the cell.
ayurveda: A highly developed system of therapeutics developed in the Hindu and Buddhist cultures of the Indian subcontinent.
B lymphocyte (B cell): One of the immune system cell types; B cells fight infection primarily by making antibodies.
bacteremia: Presence of bacteria in blood, indicating infection.
bactericidal: An agent that destroys bacteria (a type of microbe or organism).
bacteriostat: Substance that retards growth of bacteria.
balm: Fragrant ointment or aromatic oil with medicinal value.
balsam: A resinous semisolid mass or viscous liquid exuded from a plant. A “true” balsam is characterized by its high content of benzoic acid, benzoates, cinnamic acid, or cinnamates.
baroreceptor: Neural receptor sensitive to pressure and rate of change in pressure; stretch receptor; found in the aortic arch and carotid sinuses.
basal metabolic rate: The rate of metabolism when the body is at rest.
basal cell carcinoma: Common, usually curable, slow-growing malignant tumor on the skin.
basal rosette: Leaves radiating directly from the crown of the root.
baseline: The first or starting measurement in a study. New measurements of blood values are compared to this starting value.
basophil: A type of white blood cell that is involved in allergic reactions.
bed-wetting: See enuresis.
Bell’s palsy: Paralysis of muscles on one side of the face and the inability to close eye, sometimes with loss of taste and excess sensitivity to noise.
benign: Consisting of a localized mass of nonmalignant specialized cells within connective tissue that do not invade and destroy tissue or spread throughout body.
berry: Small, fleshy fruit or dry seed or kernel of various plants.
beta-blocker: Drug that decreases heart activity by affecting receptors of the sympathetic nervous system.
beta cells: The cells in the pancreas, which manufacture insulin.
biennial: Plant with two-year life cycle in which the vegetative first-year growth is followed by fruiting and dying during second year.
bile: Greenish liver secretion that is stored in the gallbladder until released to emulsify fats in the small intestine.
bile salts: Steroid molecules in bile that promote solubilization and digestion of fats.
bilirubin: The breakdown product of the hemoglobin molecule of red blood cells.
bilirubinemia: Excess bile pigment in blood that causes jaundice.
binomial: Standard scientific name for an organism in Latin.
bioavailability: The amount of drug that is available to the target tissue after administration; this may not be 100% due to degradation or alteration before reaching the target tissue.
biopsy: A diagnostic test in which tissue or cells are removed from the body for examination under a microscope.
biopharmaceutics: The science and study of the ways in which the pharmaceutical formulation of administered agents can influence their pharmacodynamic and pharmacokinetic behavior.
biotransformation: Chemical alteration of an agent that occurs by virtue of the sojourn of the agent in a biological system. Pharmacodynamics involves the chemical effects of a drug on the body; biotransformation involves the chemical effect of the body on a drug. “Biotransformation” and “detoxication” are not synonyms: The product of a biotransformation may be more, not less, biologically active, or potent, than the starting material.
biotranslocation: The movement of chemicals through biological organisms.
bitters: Herbs with a bitter taste.
blade: Broad, expanded part of a leaf.
bleeding time: The time required for the cessation of bleeding from a small skin puncture as a result of platelet disintegration and blood vessel constriction. Ranges from 1 to 4 minutes.
blennorrhagia: Heavy discharge of mucus, especially from the urethra.
blepharitis: Inflammation, scaling, and crusting of eyelids.
blister: External swelling that contains watery fluid and blood or pus, caused by friction.
blocking antibody: Antibody whose production is induced by cancer cells or tissue transplants and that blocks the killing of those cells by cytotoxic T cells.
blood count: Measurement of the number of red cells, white cells, and platelets in a sample of blood.
blood pressure: The force exerted by blood as it is pumped by the heart and presses against and attempts to stretch blood vessels.
blood poisoning: Prolonged invasion of the bloodstream by pathogenic bacteria due to infectious disease or skin lesions; bacteremia; septicemia; toxemia.
blood-brain barrier: Group of anatomical barriers and transport systems that tightly control types of substances entering the extracellular space of the brain.
boil: Tender, inflamed, pustulant area of skin, usually due to staphylococcus infection; furuncle.
bolus: Single, large mass of a substance.
bone marrow: The inner core of bone that produces blood cells.
botany: Branch of biology dealing with life, structure, growth, and classification of plants.
bract: Leaflike structure growing below or encircling a flower cluster or flower.
bradycardia: Slowing of the heart rate to under 50 beats per minute.
bradykinin: Peptide vasodilator that increases capillary permeability and probably stimulates pain receptors.
bromeliad: Member of the Pineapple family of plants, usually epiphytic, with stiff, leathery leaves and spikes of bright flowers.
bronchial asthma: See asthma.
bronchitis: Inflammation of the walls of the bronchi in the lungs due to virus or bacteria, causing coughing and production of sputum.
bronchodilator: Substance that relaxes bronchial muscle to open air passages to the lungs.
bronchospasm: Muscular contraction that narrows the bronchi and causes difficulty especially in exhalation .
bruit: Any abnormal sound or murmur heard with a stethoscope.
bryophyte: Any member of the division of nonvascular plants, including mosses and liverworts.
bubo: Swollen and inflamed lymph node in armpit or groin.
bulb: Dormant underground bud stage of some plants.
bulimia: Psychogenic syndrome of overeating followed by vomiting.
bunion: Swelling of the joint between the big toe and the first metatarsal.
bursa: A sac or pouch that contains a special fluid that lubricates joints.
bursitis: Inflammation of a bursa.
cachexia: Weight loss, weakness, and debility associated with chronic disease.
calcinosis: Abnormal deposit of calcium salts in tissue.
calcitonin: Peptide hormone secreted by the thyroid that reduces excess of calcium in the blood by depositing it in bone.
calculus: Pebblelike mass, such as gallstone or kidney stone, formed within the body; hard tartar layer formed on teeth by plaque.
callus: Hard thickening of an area of skin undergoing rubbing, on hands or feet; mass of tissue forming around fractured bone ends.
calorie: A unit of heat. A nutritional calorie is the amount of heat necessary to raise 1 kg of water one degree C.
calyx: The sepals or outer layer of floral leaves.
cambium: Layer of formative cells beneath the bark of a tree.
cancer: General term for more than 100 diseases characterized by abnormal and uncontrolled growth of cells.
cancrum: Ulceration of the lip or mouth; canker.
candidiasis: Yeastlike fungus infection in the mouth and moist areas of the body; see also thrush.
canker: See cancrum.
capsule: A dry fruit, opening when ripe, composed of more than one carpel.
carbohydrate: Sugars and starches.
carbuncle: Staphylococcus infection of the skin that causes boils with multiple drainage channels.
carcinogen: Any agent or substance capable of causing cancer.
carcinogenesis: The development of cancer caused by the actions of certain chemicals, viruses, and unknown factors on primarily normal cells.
carcinoma: Cancer in epithelium lining skin or internal organs.
cardiac output: Volume of blood pumped by either ventricle per minute.
cardiac remedy: An herbal remedy that has a beneficial action on the heart. Some of tile remedies in this group are powerful cardioactive agents such as foxglove; others are gentler, safer herbs such as hawthorn and motherwort.
cardiac arrest: Abrupt cessation of heartbeat, causing loss of pulse, consciousness, and breathing.
cardiac stenosis: Abnormal narrowing of a heart valve.
cardiomyopathy: Chronic viral, congenital, or other disorder that affects heart muscle and causes heart failure, arrhythmias, or embolisms.
cardiopulmonary: Pertaining to the heart and lungs.
cardiotonic: A compound that tones and strengthens the heart.
carditis: Inflammation of the heart.
caries: Decay of bone tissue, especially tooth; cavity.
carminative: Plants rich in aromatic volatile oils that stimulate the digestive system to work properly and with ease, soothing the gut wall, reducing any inflammation, easing griping pains, and helping the removal of gas from the digestive tract.
carotene: Fat-soluble plant pigments. Some carotenes can be converted into vitamin A by the body.
cartilage: A type of connective tissue that acts as a shock absorber at joint interfaces.
carpal tunnel syndrome: Compression of the median nerve entering the palm of the hand that causes pain and numbing in the middle and index fingers .
castor oil: Unpleasant-tasting, irritant laxative or cathartic.
catalyst: A chemical that increases the rate of a chemical reaction without itself being consumed.
cataract: Opacity of eye lens that causes blurred vision, especially in the elderly.
catarrh: Excessive secretion of thick phlegm or mucus by the mucous membrane of the nose.
catecholamines: The chemically similar neurotransmitters dopamine, epinephrine, and norepinephrine.
cathartic: A substance that stimulates the movement of the bowels, more powerful than a laxative.
catheter: A device that allows drugs to be given on an ongoing basis.
ceiling: The maximum biological effect that can be induced in a tissue by a given drug, regardless of how large a dose is administered.
cell-mediated immunity: Specific immune response mediated by cytotoxic T lymphocytes.
cephalalgia: See headache.
cephalic: Remedy for disorders of the head; referring or directed toward the head.
cerebral hemorrhage: Bleeding from the cerebral artery into brain tissue.
cerebral: Pertaining to the largest part of the brain, the cerebrum.
chelating agent: An organic compound capable of binding metals.
chemoreceptor: A molecular structure on the surface of a cell that is sensitive to chemical substances, such as epinephrine, released by nerve cells.
chemotaxis: Movement or response of cells to chemicals.
chemotherapy: Drug treatment of parasitic or neoplastic disease in which the drug has a selective effect on the invading cells or organisms.
chemotype: The same botanical species occurring in other forms due to different conditions of growth, such as climate, soil, and altitude.
Cheyne-Stokes respiration: Cyclical slowing of breathing to cessation, then speeding up to peak.
chilblain: Red, round, itchy swelling of skin on fingers or toes due to exposure to cold.
chiropractic: Treatment method using manipulation of the muscular and skeletal systems, especially the spine.
chlamydia: Sexually transmitted, viruslike microorganism causing conjunctivitis, urethritis, and cervicitis.
chlorophyll: Pigment in chloroplast, needed for photosynthesis.
chloroplast: Membrane-bound organelle that is the site of photosynthesis.
cholagogue: A compound that stimulates the contraction of the gallbladder.
cholecystitis: Inflammation of the gallbladder.
cholecystokinetic: Agent that stimulates the contraction of the gallbladder.
cholecystokinin (CCK): A peptide hormone secreted by the small intestine.
cholelithiasis: Presence of gallstones.
choleretic: Aids excretion of bile by the liver, so there is a greater flow of bile.
cholestasis: The stagnation of bile within the liver.
cholesterol: Steroid molecule that is a precursor of steroid hormones and bile salts, a component of plasma membranes, and present in fat and blood.
cholinergic: Pertaining to the parasympathetic portion of the autonomic nervous system and the release of acetylcholine as a transmitter substance.
chorionic: Referring to the chorion or membrane enclosing the fetus.
chromatography: Separation of chemical compounds.
chronic: Long term or frequently recurring.
chronic fatigue syndrome: Persistent, extreme exhaustion and weakness due to unknown causes.
chronotropic effect: An effect that changes the heart rate (i.e., the time between P-waves).
chyme: Solution of partially digested food in the lumen of the stomach and intestines.
cicatrisant: An agent that promotes healing by the formation of scar tissue.
cicatrix: See scar.
cirrhosis: Progressive liver condition from various causes.
claudication: Cramping pain from inadequate blood supply to muscle.
climacteric: Physical and emotional changes as sexual maturity gives way to cessation of reproductive function in females and testosterone decrease in males.
clot: Soft, thickened lump formed in liquid, especially blood.
clinical therapeutic index: An index of relative safety or relative effectiveness that cannot be defined explicitly and uniquely, although it is presumed that the same quantifiable and precise criteria of efficacy and safety will be used in comparing drugs of similar kinds.
clinical trial: The systematic investigation of the effects of materials or methods, according to a formal study plan and generally in a human population with a particular disease or class of diseases.
club moss: Any of various small, non-seed-bearing vascular plants with cone-like, spore-bearing structures on top of stems.
clubbing: Thickening of tissue at the base of a fingernail or toenail, especially enlargement of a fingertip.
CNS: Central nervous system.
coccus: Spherical bacterium.
coenzyme: Nonprotein organic molecule that temporarily joins with an enzyme during reaction, is not consumed in reaction, and can be reused until degraded; cofactor.
cold sore: Small swelling or eruption of skin around lips that dries to leave a crusty patch; fever blister.
colic: Pain due to contraction of the involuntary muscles of the abdominal organs.
colitis: Any inflammation of the colon, causing diarrhea and lower abdominal pain.
collagen: Extremely strong fibrous protein that functions as a structural element in connective tissue, tendons, and ligaments.
collagen disease: A disease characterized by changes in the makeup of connective tissue: lupus, rheumatic fever, rheumatoid arthritis, and scleroderma.
colloid: An extremely fine particle suspended in a surrounding medium.
collyrium: Medicated solution used to bathe eyes.
coma: Prolonged state of deep unconsciousness from which patient cannot be roused.
comparison trial: A trial in which experimental drugs are tested against each other or against an approved drug.
complement: Set of enzymes in the bloodstream that work with antibodies to attack foreign cells and bacteria.
complete blood count (CBC): Series of tests including cell counts, hematocrit, hemoglobin, and cell volume measurement.
compliance: The extent to which a patient agrees to and follows a prescribed treatment regimen.
compress: Moistened pad of folded cloth, often medicated, applied with heat, cold, or pressure to soothe a body part.
concrete: A concentrated, waxy, solid or semisolid perfume material prepared from previously live plant matter, usually using a hydrocarbon type of solvent.
cone: Reproductive structure of certain nonflowering plants with overlapping scales or bracts containing pollen, ovules, or spores.
congestion: Accumulation of blood within an organ; clogging of the upper respiratory system with mucus.
congestive heart failure: Inability of the heart to adequately supply blood to body tissue, often due to weakening of cardiac muscle, causing body swelling and shortness of breath.
conifer: Cone-bearing gymnosperm, usually with narrow, needlelike or small, scalelike leaves.
conjunctivitis: Inflammation of mucous membrane covering front of eye, often with discharge of pus; pinkeye.
connective tissue: The type of tissue that performs the function of providing support, structure, and cellular cement to the body.
constipation: Infrequent, difficult, often painful bowel movements with hard feces; irregularity.
contagious: A disease that can be transferred from one person to another by direct contact.
contraceptive: Medication or device to prevent conception.
continuous infusion: Uninterrupted introduction of fluid other than blood into a vein.
contractility: Refers to the strength of heart muscle contraction. This is controlled by the autonomic nervous system. The sympathetic nervous system increases and the parasympathetic nervous system decreases the strength of a contraction.
controlled trial: Trial in which one group gets the experimental drug and another group gets either a placebo or an approved drug therapy.
contusion: Surface injury in which skin is not broken; bruise.
convulsion: Involuntary muscle contraction that causes contorted movements of body and limbs.
corm: Underground stem base that acts as a reproductive structure.
corn: Area of hard or thickened skin on or between the toes.
corolla: The petals of a flower considered as a whole.
coronary: Of or pertaining to arteries of the heart. coronary heart disease: Serious condition affecting the coronary arteries.
coronary insufficiency: The right and left coronary arteries supply blood to the heart. Flow is considered insufficient if it cannot meet the needs of the heart.
corpus luteum: The remains of the egg follicle after ovulation.
cortical: Involving external layers of brain.
corticosteroid drugs: A group of drugs similar to natural corticosteroid hormones that are used predominantly in the treatment of inflammation and to suppress the immune system.
corticosteroid hormones: A group of hormones produced by the adrenal glands that control the body’s use of nutrients and the excretion of salts and water in the urine.
cortisol: A steroid hormone secreted by the adrenal cortex that regulates organic metabolism by converting fats and proteins to glucose.
corymb: Flat-topped or convex cluster of flowers in which the outer flowers open first.
cotyledon: First or second leaf of a seedling.
cough: Violent exhalation of irritant particles or congestive mucus from the respiratory system; tussis.
counterirritant: An application to the skin that relieves deep-seated pain, usually applied in the form of heat; see also rubefacient.
cramp: Prolonged painful contraction or spasm of muscle.
creatinine: A protein found in muscles and blood and excreted by the kidneys in the urine. The level of creatinine in the blood and urine provides a measure of kidney function.
crepitation: Soft crackling sound heard in the lungs through a stethoscope; rale.
crepitus: Crackling sound made by grating of bone on bone or on cartilage, especially in an arthritic joint.
CRR: Corticotropin-releasing hormone.
crick: Painful muscle spasm or cramp in neck or upper back.
crossover experiment: Each subject receives the test preparation at least once, and every test preparation is administered to every subject. At successive experimental sessions each preparation is “crossed over” from one subject to another.
Cushing’s disease: Syndrome due to excess corticosteroid hormone, causing weight gain, excess body hair, and high blood pressure.
cutaneous: Pertaining to the skin.
cuticle: Waxy layer on the outer surface of plants.
cyanosis: Bluish discoloration of skin and mucous membranes due to inadequate oxygenation.
cycad: Any of the order of gymnosperms intermediate between ferns and palms, often with a thick, columnar trunk crowned by large, tough, pinnate leaves.
cyme: Inflorescence in which the primary axis bears a single central or terminal flower that blooms first.
cyst: An abnormal lump or swelling, filled with fluid or semisolid material, in any body organ or tissue.
cytokine: Protein produced by white blood cells that acts as a chemical messenger between cells. CD8 (T-suppressor) cells release a cytokine that appears to block HlV replication in infected cells, at least until the advanced stage of HTV disease.
cytokinin: Plant hormone that promotes cell division.
cytomegalovirus: A virus in the herpes family that causes enlargement of epithelial cells and mononucleosis-like disease.
cytotoxic: Toxic to all cells.
cytotoxic T lymphocyte (CTL): A lymphocyte that is able to kill foreign cells that have been marked for destruction by the immune system.
cytotoxin: Substance that has a toxic effect on certain cells, used against some tumors.
debility: Weakness, lack of tone.
deciduous: Any plant that sheds all its leaves once each year.
decoction: An herbal preparation in which the plant material (usually hard or woody) is boiled in water and reduced to make a concentrated extract.
decongestant: Substance used to reduce nasal mucus production and swelling.
deficiency disease: Any disease, such as beriberi, caused by nutritional deficiency.
dehiscence: Splitting open of a wound.
dehydration: Deficiency or loss of water in body tissues marked by thirst, nausea, and exhaustion.
delirium: Acute mental disorder due to organic brain disease, causing hallucinations, disorientation, and extreme excitation.
dementia: Senility; loss of mental function.
demineralization: Loss of minerals from the bone.
demulcent: An herb rich in mucilage that soothes and protects irritated or inflamed tissue.
deodorant: Corrects, masks, or removes unpleasant odors.
dependence: A somatic state that develops after chronic administration of certain drugs; this state is characterized by the necessity to continue administration of the drug in order to avoid the appearance of uncomfortable or dangerous (withdrawal) symptoms.
depressant: drug that lowers nervous or functional activity; sedative.
depurative: Helps combat impurity in the blood and organs.
dermal: Pertaining to the skin.
dermatitis: Skin inflammation.
detumescence: Reduction or subsidence of swelling.
diabetes: Diabetes mellitus.
dialysis: A technique using sophisticated machinery to remove waste products from the blood and excess fluid from the body in the treatment of kidney failure.
diaphoretic: Promotes perspiration, enabling the skin to eliminate waste from the body, thus helping the body ensure a clean and harmonious inner environment.
diarrhea: Frequent bowel evacuation, especially of soft or liquid feces.
diastole: Period of the cardiac cycle in which ventricles are not contracting.
diastolic pressure: Minimum blood pressure during cardiac cycle.
dicot: See dicotyledon.
dicotyledon: Angiosperm having two seed leaves or cotyledons; dicot.
digestion: Process of breaking down large particles and high molecular- weight substances into small molecules.
digestive: Substance that promotes or aids the digestion of food.
diphtheria: Acute, highly contagious bacterial infection of the throat that can cause death from respiratory obstruction or carditis.
disinfectant: Cleansing agent that destroys bacteria and other microorganisms, used on surfaces and surgical tools.
disintegration time: The time required for a tablet to break up into granules of specified size (or smaller), under carefully specified test conditions.
dissolution time: The time required for a given amount (or fraction) of drug to be released into solution from a solid dosage form.
diuretic: Increases the production and elimination of urine.
diverticulum: Saclike out-pouching of the wall of the colon.
diverticulitis: Colonic diverticulosis with inflammation.
diverticulosis: Condition characterized by the existence of diverticular sacs at weak points in the walls of the alimentary tract, especially the intestine.
dizziness: Feeling off balance, unstable, confused, as though whirling in place.
dopamine: A catecholamine neurotransmitter, precursor of epinephrine and norepinephrine.
dorsal: Pertaining to the back.
dormancy: Period of time in which growth ceases.
dosage form: The physical state in which a drug is dispensed for use.
dose: The quantity of drug, or dosage form, administered to a subject at a given time.
double-blind study: A way of controlling against experimental bias by ensuring that neither the researcher nor the subject knows when an active agent or a placebo is being used.
douche: Introduction of water and/or a cleansing agent into the vagina with the aid of a bag with tubing and a nozzle attached.
dressing: Protective or healing material applied externally to a wound or a diseased body part.
dromo: Refers to speed.
dromotropic effect: A change in the amount of time it takes the heart to complete one beat.
dropsy: Excess of fluid in the tissues.
drug: Substance that affects the structure or functional processes of an organism, especially to prevent or treat diseases or relieve symptoms.
drupe: A fleshy fruit, with one or more seeds, each surrounded by a stony layer.
dysentery: Infection of the intestinal tract that causes severe diarrhea mixed with blood and mucus.
dysfunction: Abnormal function .
dysmenorrhea: Painful, difficult menstruation.
dyspepsia: Digestive disorder with abdominal pain and gas after eating, sometimes with nausea and vomiting; indigestion.
dysplasia: Any abnormality of growth.
dyspnea: Labored or difficult breathing; breathlessness.
dystrophy: Organ or muscle disorder caused by insufficient nourishment or a hereditary disorder.
ecchymosis: Bluish black mark on skin from release of blood into tissues, usually due to injury; black-and-blue mark.
eclampsia: Convulsions, especially due to toxemia during pregnancy.
ectopic pregnancy: State in which a fertilized egg implants at a site other than the uterus.
edema: Excessive accumulation of fluid in tissues; dropsy.
ED50: Median effective dose.
electrocardiogram (ECG): Machine that measures and records the activity of the heart.
electroencephalogram (EEG): Machine that measures and records brain waves.
electrolyte: Substance that ionizes in solution and conducts electric current.
electuary: Medication mixed with honey.
elimination diet: A diet that eliminates allergic foods.
elimination half-life: The time it takes for the body to eliminate or break down half of a dose of a pharmacologic agent.
elixir: Substance that contains alcohol or glycerin, used as solution for bitter or nauseating drugs.
elliptical: Shaped like an ellipse, or regular curve.
embolism: Obstruction of an artery by a lodged blood clot, fat, air, or foreign body carried by circulating blood.
embolus: Mass of matter that obstructs blood flow.
emesis: Vomiting; vomited matter.
emetic: Substance that induces vomiting.
emmenagogue: Stimulates menstrual flow and activity.
emollient: Soothes and softens external tissue.
empyema: Accumulation of pus in a body cavity, especially the pleural cavity.
emulsification: Maintenance of lipid droplets in solution.
emulsify: The dispersement of large globules into smaller, uniformly distributed particles.
endemic: Disease that is constantly present in a particular region but generally under control.
endocarditis: Inflammation and damage to the heart cavity lining due to bacterial infection or rheumatic fever.
endocrine gland: Ductless organ that synthesizes hormones and releases them directly into the bloodstream.
endocrine system: All ductless glands in the body.
endocrinology: Study of the endocrine glands and hormones.
endometrium: The mucous membrane lining the uterus.
endometriosis: A condition in which tissue similar to that normally lining the uterus is found outside of the uterus, usually the ovaries, fallopian tubes, and other pelvic structures.
endorphin: Neurotransmitter that exhibits painkilling activity.
enervation: Weakness, lack of energy.
engorgement: Congestion of a part of tissues, or fullness (as in the breasts).
enteric-coated: A way of coating a tablet or capsule to ensure that it does not dissolve in the stomach and so can reach the intestinal tract.
enuresis: Involuntary urination, especially at night, usually functional in nature; bed-wetting.
enzyme: Complex protein that is produced by living cells and catalyzes specific biochemical reactions.
eosinophil: A type of white blood cell, called a granulocyte, that can digest microorganisms.
epidemiology: Study of causes and control of epidemics.
epilepsy: One of various brain disorders that cause recurrent, sudden convulsive attacks.
epinephrine: Hormone released by the adrenal medulla that elevates blood sugar and initiates the fight-or-flight response; adrenaline.
epiphyte: Nonparasitic plant growing upon another plant for support.
epistaxis: Bleeding from the nose.
erysipelas: A skin infection from streptococcus bacteria that causes inflammation, swelling, and fever.
erythema: A superficial redness of the skin due to excess of blood.
erythrocyte: A red blood cell whose primary function is to carry oxygen to cells.
erythropoiesis: Formation of erythrocytes.
erythropoietin: Hormone secreted mainly by the kidneys that stimulates erythrocyte production.
essential fatty acid (EFA): A fatty acid that the body cannot manufacture, e.g. linoleic and linolenic acids.
essential oil: A volatile oil obtained from the leaves, stem, flower, or other part of plants, usually carrying the odor characteristic of the plant.
estrogen: Any of several steroid hormones produced chiefly by the ovaries and responsible for promoting estrus and the development and maintenance of female secondary sex characteristics.
etiology: Science of causes and origins of diseases.
evergreen: Plant that maintains functional green foliage throughout year.
excretion: The elimination of waste products from a cell, tissue, or the entire body.
exfoliant: A product or ingredient whose purpose is to remove unwanted tissue or waste products from the skin and other body surfaces.
exfoliate: To shed cells from the epithelium layer of the skin or mucosa.
exocrine gland: A gland that secretes through a duct.
exophthalmic goiter: Enlargement of the thyroid gland accompanied by protrusion of the eyeballs from their orbits.
expectorant: Soothes bronchial spasm and loosens mucous secretions, helping dry, irritating coughs.
extracellular: The space outside the cell, composed of fluid.
exudate: Escaping fluid or semifluid material that oozes from a space that may contain serum, pus, and cellular debris.
eyewash: Medicinal solution that soothes eyes.
fatty acid: Organic compound whose carbon chain ends in a carboxyl group.
febrifuge: Substance that relieves or reduces fever.
feces: Digestive waste products.
feedback inhibition: Mechanism that maintains constant secretion of a product by exerting inhibitory control.
fern: Nonflowering, vascular plant having roots, stems, and fronds and reproducing by spores instead of seeds.
fever: Rise in body temperature above normal 37 degrees.
fibrillation: Rapid, uncontrolled irregular twitching of heart muscle.
fibroblastic: Pertaining to fibroblasts, or connective tissue cells.
fibrocystic changes: Formation of benign cysts of various sizes in the breast.
fibrosis: Thickening and scarring of connective tissue due to injury or inflammation.
first-degree burn: Reddening of the outer layer of skin.
first pass effect: The biotransformation and/or excretion of a drug by hepatic, including biliary, mechanisms following absorption of the drug from the gastrointestinal tract, before the drug gains access to the systemic circulation.
fissure: Crack in membrane lining.
fistula: Abnormal passage that leads from an abscess or cavity to the skin or to another abscess or cavity, caused by disease or injury.
fixative: A material that slows down the rate of evaporation of the more volatile components in a perfume composition.
fixed oil: A name given to vegetable oils obtained from plants that, in contradistinction to essential oils, are fatty, dense, and nonvolatile, such as olive and sweet almond oils.
flatulence: Expulsion of intestinal gas through mouth by belching or through anus by passing flatus.
flatus: Intestinal gas.
flavonoid: Plant pigment that exerts a wide variety of physiological effects in the human body.
floret: Small flower; one of a number of individual flowers comprising the head of a composite plant.
flowering plant: Any angiosperm that produces flowers, fruit, and seeds in an enclosed ovary.
foliage: Leaves of plant or tree.
follicle: Saclike structure that forms inside an ovary when an egg is produced.
free radical: Highly reactive molecule that can bind to and destroy cellular compounds.
frond: Fern or palm foliage.
fructose: Yellowish to white, crystalline, water-soluble sugar found in many fruits.
fruit: Mature ovary of a flowering plant, sometimes edible.
functional cyst: A benign cyst that forms on an ovary and usually resolves on its own without treatment.
fungicidal: Prevents and combats fungal infection.
fungus: Unicellular or filamentous organism, formerly classified with plants.
galactagogue: Increases secretion of milk.
gallstone: Hard mass of bile pigments, cholesterol, and calcium salts in the gallbladder.
gamma globulin: The part of blood serum that contains antibodies, used in temporary prevention of infectious diseases.
gargle: Antiseptic, often medicated, liquid used to rinse mouth and throat; mouthwash.
gastrin: Digestive system hormone that stimulates hydrochloric acid release by stomach and secretion of digestive enzyme by pancreas.
genus: Category of closely related species ranking below family and above species.
germicidal: Destroys germs or microorganisms such as bacteria.
germinate: Sprout and start to grow from spore or seed.
gingivitis: Inflammation of gums, sometimes with bleeding.
glaucous: Covered with a fine white, often waxy film that rubs off.
glioma: Cancer of nerve tissue.
glomerular filtration rate (GFR): Milliliters of plasma per minute filtered through the kidney.
glomerulonephritis: Potentially fatal streptococcal infection of the kidney.
glucagon: Pancreatic hormone that increases blood glucose levels.
glucocorticoid: Adrenal cortex hormone that affects salt and water metabolism and stimulates conversion of noncarbohydrates to carbohydrates.
glucose: A monosaccharide that is found in the blood and is one of the body’s primary energy sources.
glutamic acid: An amino acid that may be a brain neurotransmitter.
gluten: One of the proteins in wheat and certain other grains that gives dough its tough, elastic character.
glycerin: See glycerol.
glycerol: Syrupy liquid prepared by hydrolysis of fats and oils for use as a skin lotion.
glycogen: White polysaccharide sugar, derived from glucose, that is the principal form in which carbohydrate is stored in tissue.
glycoprotein: Carbohydrate-protein complex.
glycoside: Plant chemical that consists of molecules made up of two sections, one of which is a sugar.
glytosuria: Excretion of excess sugar in urine, as in diabetes.
goblet cell: A goblet-shaped cell that secretes mucus.
goiter: Swollen neck due to an enlarged thyroid gland.
gonadotropin: A hormone that promotes gonad (sex gland) growth and function.
granulocyte: A cell type of the immune system filled with granules of toxic chemicals that enable it to digest microorganisms. Basophils, neutrophils, and eosonophils are examples of granulocytes.
granuloma: Nodule of connective tissue and capillaries associated with tuberculosis, syphilis, or nonorganic foreign bodies.
ground substance: The thick, gel-like material in which the cells, fibers, and blood capillaries of cartilage, bone, and connective tissue are embedded.
gum: A class of carbohydrates that swell in the presence of water and increase the thickness of water-based products.
gymnosperm: Member of the division of seed plants having ovules on open scales, especially cones.
half-life: The time required for the decay of half a sample of a radioactive substance; may also apply to pharmacologic agents.
hallucinogenic: Causes visions or delusions.
hay fever: Common, usually seasonal allergy to plant pollen that causes sneezing, runny nose, and watery eyes.
HDL: High-density lipoprotein.
headache: Pain within the skull, commonly due to stress or fatigue; cephalalgia.
heart failure: Inadequate pumping of the heart ventricles due to coronary thrombosis, hypertension, or arrhythmia; congestive heart failure .
heart murmur: Blowing or swishing noise produced by blood passing through a defective heart valve.
heartburn: Pain rising from abdomen to throat, often accompanied by bitter fluid in the mouth; pyrosis.
heartwood: The central portion of a tree trunk.
helper T cell: White blood cell that helps in the immune response.
hematocrit: The percentage of packed red blood cells in a given volume of blood. Normal ranges: women 37-43%, men 43-49%.
hematuria: Blood in the urine.
hemorrhage: Outflow of blood from a ruptured blood vessel,
especially internal bleeding. hemorrhoid: An enlarged vein in the anus wall, especially due to prolonged constipation or diarrhea, characterized by fissure, painful swelling, and bleeding; piles.
hemostatic: A substance that checks bleeding.
heparin: Natural anticoagulant produced by liver cells as a polysaccharide.
hepatic: Pertaining to the liver.
hepatitis: Inflammation of the liver, due to a virus transmitted by food or drink (infectious hepatitis), blood on a needle, or transfusion (serum hepatitis), causing fever and jaundice.
hepatomegaly: Enlargement of the liver.
hernia: Protrusion of tissue or an organ outside the cavity it normally occupies, especially in the lower abdomen, due to physical strain or coughing.
herniated disk: Slipped disk.
Herpes: Herpes simplex; small viral blisters on the skin.
Herpes simplex: Virus in the herpes family; non-venereal blisters on mucous membranes that can cause conjunctivitis, vaginal inflammation, or cold sores; herpes.
Herpes zoster: Virus in the herpes family characterized by vesicles, often with severe pain along distribution of nerve; shingles.
hiccup: Characteristic sound made by abrupt involuntary lowering of the diaphragm and closing of the upper end of the trachea.
high-density lipoprotein (HDL): Lipid-protein aggregate with a low proportion of lipid or cholesterol that removes cholesterol from arteries.
histamine: Amine derived from the amino acid histidine that is released in allergic reaction, causing dilation of the blood vessels.
HIV: Human immunodeficiency virus.
homeostasis: Maintenance of constant internal environment.
hormone: A secretion of an endocrine gland that controls and regulates functions in other parts of the body.
humoral: Immunity defense against disease by antibodies in body fluids.
hybrid: A plant originating by fertilization of one species or subspecies by another.
hydrocarbon: Compound containing only hydrogen and carbon.
hydrocele: Accumulation of watery fluid, especially about the testis.
hydrochloric acid: Acid secreted by stomach during digestion.
hyperglycemia: High blood sugar level.
hypergonadotropic: Increased production of gonad-stimulating hormone from the anterior pituitary gland.
hyperlipidemic: Elevation of cholesterol and triglycerides in the blood.
hyperpigmentation: Abnormally increased pigmentation.
hypersecretion: Excessive secretion.
hypersensitivity: Allergic reaction.
hypertension: High blood pressure.
hypertensive: A substance that causes a rise in blood pressure.
hyperthermia: Exceptionally high body temperature of 105 degrees F or above; fever induced as treatment.
hyperthyroidism: Overactivity of the thyroid gland that causes rapid heartbeat, sweating, tremors, weight loss, and anxiety.
hypertrophy: Increase in size of tissue or organ due to enlargement of cells.
hyperventilation: Abnormally rapid breathing that lowers carbon dioxide concentration in the blood.
hypnotic: A drug that produces a state clinically identical to sleep by means of action in the central nervous system.
hypochlorhydria: Insufficient gastric acid Output.
hypochondria: Obsession with real and imagined physical ailments.
hypoglycemia: Low blood sugar.
hypoglycemic: Plant remedy that lowers abnormally elevated blood sugar.
hypogonadism: Below normal gonad (sex gland) function .
hypokalemia: Low potassium levels in the blood.
hypotension: Low blood pressure.
hypotensive: Plant remedy that lowers abnormally elevated blood pressure.
hypothalamus: An area of the forebrain that regulates pituitary gland secretion, among many other functions.
hypothyroidism: Subnormal thyroid gland activity that can lead to cretinism if present at birth.
hypoxia: An inadequate supply of oxygen.
iatrogenic: Meaning literally “physician produced,” the term can be applied to any medical condition, disease, or other adverse occurrence that results from medical treatment.
idiopathic: Of unknown cause.
Ig: See immunoglobulin.
immune response: Body’s defense reaction through dual modes of antibody and cellular response.
immunity: Ability of the body to recognize and neutralize foreign matter, either natural or acquired .
immunoglobulin (Ig): Any of five classes of antibodies: Igg, Igm, Iga, and Igf.
immunodeficiency: A condition resulting from a defective immune system.
immunomodulator: Substance hoped to strengthen the immune system and help the body fight off opportunistic infections or other diseases. Not necessarily used to stimulate the immune system.
immunostimulant: A plant that stimulates some aspect of immune system functioning.
impairment: Damage to or weakening of body part or function.
in vitro: Latin for “in glass.” An artificial environment created outside a living organism, used to study a disease or process.
in vivo: Latin for “in life.” Study conducted within a living organism-e.g., animal or human study.
inborn immunity: Congenital resistance to a specific disease.
incidence: The number of new cases of a disease that occur during a given period (usually years) in a defined population.
inclusion/exclusion criteria: The medical or other reasons why a person mayor may not be allowed to enter a clinical trial.
incontinence: Involuntary passage or leakage of urine.
incubation period: Time between entry of disease organisms into the body and onset of disease symptoms.
infarction: Death of tissue due to Oxygen deprivation.
infestation: Attack on body by parasitic microorganism.
inflorescence: Flowering structure above the last stem leaves (including bracts and flowers).
infusion: An herbal remedy prepared by steeping the plant material in water.
inorganic: In chemistry, the term refers to compounds that do not contain carbon.
inotropic effect: Ino- is a prefix that refers to muscle. Inotropic effects are ones that change the strength of contraction of the heart muscle.
insomnia: Inability to fall asleep or to remain asleep.
insulin: Pancreatic hormone that regulates blood sugar level.
interferon: Substance produced by infected cells that inhibits specific viral growth.
interleukin: A natural blood substance that helps immune system cells to communicate.
intestinal malabsorption: A condition in which the nutrients found in food are not absorbed by the body.
intrinsic activity: The property of a drug that determines the amount of biological effect produced per unit of drug-receptor complex formed.
investigational new drug (IND): A drug allowed by the FDA to be used in clinical trials but not approved for commercial marketing.
irreversible: Impossible to halt or reverse by treatment.
irritable bowel syndrome: Recurrent chronic abdominal pain with constipation and/or diarrhea caused by abnormal contractions of colon muscles; spastic colon.
irritant: A substance that produces redness, itching, swelling, or blisters on the skin.
ischemia: Reduced blood supply to an organ or tissue.
jaundice: A condition caused by elevation of bilirubin in the body and characterized by yellowing of the skin.
keratin: An insoluble protein found in hair, skin, and nails.
kidney stone: Hard, pebble-like mass in kidney that causes pain and blood in urine; nephrolithiasis; renal calculus.
killer T cells: A class of immune system cells that function to kill cancer- and virus-infected cells; see also natural killer cells.
kinin: Vasodilatory polypeptide.
laceration: Tear in flesh, especially with irregular edges.
lactase: An enzyme that breaks down lactose into the monosaccharides glucose and galactose.
lactose: One of the sugars present in milk. It is a disaccharide.
lanceolate: Lance-shaped, oval, and pointed at both ends (usually a leaf shape).
laparoscopy: A surgical procedure in which a slender, light-transmitting telescope is used to view the pelvic organs.
larvicidal: An agent that prevents and kills larvae.
laryngitis: Inflammation of the larynx and vocal cords.
latency: The period when an organism is in the body but is not producing any ill effects.
laxative: Stimulating bowel movements.
LDL: See low-densily lipoprotein.
lecithin: Phospholipid in nerve tissue and blood.
legume: A fruit consisting of one carpel, opening on one side, such as a pea.
lenticel: Spongy area of bark on a woody plant that allows exchange of gases between the stem and the atmosphere.
lesion: Any localized, abnormal change in tissue formation.
lethargy: A feeling of tiredness, drowsiness, or lack of energy.
leukocyte: White blood cell.
leucocytosis: An increase in the number of white blood cells above the normal limit.
leucoplakia: A precancerous lesion usually seen in the mouth that is characterized by a white patch.
leukemia: Overproduction of abnormal white blood cells by bone marrow and other blood-forming organs.
leukocytosis: Abnormal level in number of white blood cells, usually due to infection.
leukopenia: Reduction in number of white blood cells to below normal level.
leukotriene: Inflammatory compound produced when oxygen interacts with polyunsaturated fatty acids.
lichen: Fungus in symbiotic union with an alga.
lignin: Organic substance that serves as a binder for cellulose fibers in wood.
ligulet: A narrow projection from the top of a leaf sheath in grasses.
lipase: A fat-splitting enzyme.
lipid: A fat, phospholipid, steroid, or prostaglandin.
lipolytic: Causing lipolysis, the chemical disintegration or splitting of fats.
lipoprotein: A molecule combining protein and lipid.
lipotropic: Promoting the flow of lipids to and from the liver.
liverwort: Any of various small, flat bryophytes, usually on logs, rocks, or soil in moist areas.
lotion: An emollient emulsion, usually of the water-in-oil type.
low-density lipoprotein (LDL): Protein-lipid aggregate that is a major cholesterol carrier in plasma.
lubricant: A greasy substance applied to reduce friction on a body surface.
lumen: Cavity within a tubular structure.
lumpectomy: Surgery to remove only the abnormal breast.
lycopod: See club moss.
lymph: Colorless fluid derived from blood and carried in special ducts of lymphatic vessels.
lymphadenopathy: Swollen, firm, and possibly tender lymph glands.
lymphatic: Pertaining to the lymph system.
lymphocyte: A type of white blood cell found primarily in lymph nodes.
lymphoid tissue: Connective tissue containing lymphocytes.
lymphoma: A malignant tumor of lymph nodes that is not Hodgkin’s disease.
macerate: Soak until soft.
macrophage: A large immune system cell that roams through the blood looking for foreign matter.
macule: Discoloration or thickening of skin in contrast to the surrounding area.
malabsorption: Impaired absorption of nutrients.
malaise: General sense of being unwell, often accompanied by physical discomfort and weakness.
malignant: A term used to describe a condition that tends to worsen and eventually causes death.
malnutrition: Insufficient food consumption to satisfy bodily needs over a prolonged period.
mammogram: An X-ray of the breast.
manipulation: As a therapy, the skillful use of the hands to move a part of the body or a specific joint or muscle.
mast cell: A cell found in many tissues of the body that contributes greatly to allergic and inflammatory processes by secreting histamine and other inflammatory chemicals.
mastectomy: Surgical removal of the breast.
mastitis: Inflammation of breasts due to bacterial infection.
measles: Highly infectious viral epidemic disease, mainly in children, that causes high fever and elevated pink rash; rubeola.
melanoma: Malignant tumor of melanin-forming cells.
memory cells: T cells that have been exposed to specific antigens and are able thereafter to proliferate upon repeat exposure to the same antigens.
menstruation: The discharge of blood and tissue from the uterus that occurs when an egg is not fertilized.
metabolic rate: Level of energy expenditure.
metabolism: A collective term for all the chemical processes that take place in the body.
metabolite: A product of a chemical reaction.
metastasis: Spread of a malignant tumor far from its site of origin, usually through the vascular system.
microflora: The microbial inhabitants of a particular region e.g., the colon.
microorganism: Any living organism too small to be viewed by the unaided eye, including bacteria, viruses, protists, and some algae and fungi.
migraine: Recurrent, intense headache, often accompanied by blurred vision and vomiting, caused by contraction and dilation of arteries in tile brain.
mineralocorticoid steroid: A salt-retaining hormone of the adrenal cortex.
miscible: The ability of a gas or liquid to mix uniformly with another gas or liquid.
mitogenic: An agent that effects cell division.
mold: Multicellular filamentous fungus.
mole: Flat or raised area of brown pigment in the skin.
monoclonal: Genetically engineered antibodies specific for one particular antigen.
monocotyledon: An angiosperm having only one seed leaf; cotyledon.
monosaccharide: A simple one-unit sugar such as fructose or glucose.
moss: Any of various small bryophytes without true stems reproducing by spores and growing in velvety clusters in moist areas on rocks, trees, and the ground.
motor: Designating muscular activity stimulated by impulses from the central nervous system.
moxa: A dried herb (usually mugwort) burnt on or above the skin to stimulate an acupuncture point or to serve as a counterirritant.
mucilage: A substance containing gelatinous constituents that are demulcent.
mucin: A protein that forms mucus when mixed with water.
mucolytic: Dissolving or breaking down mucus.
mucosa: See mucous membrane.
mucous membrane: Mucus-secreting membrane lining body cavities and canals connecting with external air.
mucus: Viscid watery lubricating solution secreted by mucous membranes.
muscle relaxer: Depressant or tranquilizer that acts to relieve tension in muscles.
mutagen: External agent that increases mutation rate in cells.
myalgia: Pain in one or more muscles.
mycelium: Mass of threadlike rubes forming the vegetative parts of a fungus.
mycorrhiza: Close symbiosis between the mycelia of certain fungi and the root cells of some vascular plants.
mycosis: Fungus infection.
mycotoxin: Toxin from yeasts and fungi.
myelin sheath: A white fatty substance that surrounds nerve cells and aids in nerve impulse transmission.
myeloma: Malignancy of bone marrow.
myelosuppression: The suppression of bone marrow activity, which can cause anemia.
narcotic: A substance that induces sleep; intoxicating or poisonous in large doses.
natural immunity: Inborn lack of susceptibility to a specific disease.
natural killer cells (NK cells): Large immune system cells that attack and destroy infected and cancer-causing cells.
naturopathy: Treatment of disease that employs no surgery or synthetic drugs.
nausea: Feeling that one is about to vomit.
necrosis: Death of cells in an organ or tissue.
nectary: Organ of a plant that secretes nectar.
neoplasia: Tumor formation, characterized by a progressive, abnormal replication of cells.
neoplasm: New rumor caused by uncontrolled reproduction of abnormal cells.
nephritis: Inflammation of the kidney; Bright’s disease.
nephrotoxic: Poisonous to the kidneys.
nervine: Relaxants that ease anxiety and tension by soothing both body and mind.
neuralgia: A stabbing pain along a nerve pathway.
neurasthenia: Nervous exhaustion.
neuritis: Inflammation of nerves; neuropathy.
neuron: Functional unit of a nerve, including cell body, axon, and dendrites.
neuropathy: Any abnormal, degenerative or inflammatory state of the peripheral nervous system.
neurotransmitter: A substance that modifies or transmits nerve impulses.
neutropenia: A low number of neutrophils in the blood.
nitric oxide (NO): A potent vasodilator released by endothelial cells to signal smooth muscle cells to relax.
NK cells: See Natural killer cells.
nocturia: The disturbance of a person’s sleep at night by the need to pass urine.
nonvascular: Plant bryophyte nut dry, single-seeded fruit of various trees and shrubs consisting of kernel enclosed in hard or tough shell.
obovate: Refers to leaf shape; oval, but broader toward the apex.
occlusion: Closing or obstruction of a hollow organ or body part.
oedema: See edema.
oestrogen: See estrogen.
off label: A drug prescribed for conditions other than those indicated on the label.
ointment: Substance used to soothe or heal skin; salve; unguent.
oleo gum resin: A narural exudation from trees and plants that consists mainly of essential oil, gum, and resin.
oleoresin: A narural resinous exudation from plants; an aromatic liquid preparation extracted from botanical matter using solvents.
olfaction: The sense of smell.
open trial: A drug trial is “open” when doctors and participants know which drug is being administered. See also doubleblind srudy.
opiate: Derivative of opium that depresses the central nervous system, relieves pain, and induces sleep.
opportunistic: Designating disease or infection occurring only under certain conditions, as when the immune system is impaired.
organ: Collection of tissues joined in a strucrural unit to serve a common function.
organic disorder: Disorder associated with physiological changes in the strucrure of an organ or tissue.
organic: In the chemical sense, refers to all compounds containing carbon.
osteoarthritis: Joint cartilage disease that causes pain and impaired joint function and occurs in later life, due to overuse of a joint or as a complication of rheumatoid arthritis.
osteopathy: Treatment of disease by manipulation and massage of the musculoskeletal system.
osteoporosis: Loss of bony matrix that causes brittle bones due to injury, infection, or old age.
OTC (over the counter): Medication available without a doctor’s prescription.
ovulation: The release of an egg from one of the ovaries.
oxytocic: An agent that stimulates labor contractions.
pack: Folded, moistened, often medicated pad of cotton or cloth applied to the body or inserted into a cavity
palisade cell: Chloroplast-containing cell just below the surface of a leaf
palliative: Medicine that relieves symptoms but does not cure disease
palmate: With three or more leaflets, nerves, or lobes radiating from a central point
palpitation: Abnormally rapid or violent heartbeat, especially due to fear, exertion, neurosis, or arrhythmia
panacea: A cure-all.
pandemic: Epidemic disease that spreads to different countries over a large region
panicle: Loose, diversely branching flower clusters.
pappus: The calyx in a composite flower having feathery hairs, scales, or bristles
papule: Small, superficial bump or spot on the skin, often part of rash
parahormone: Chemical control agent that can be synthesized by more than one cell type
parasite: An organism that lives in or on another living organism while contributing nothing to its host’s welfare, often causing irritation or interfering with function
parasiticide: Prevents and destroys parasites such as fleas and lice
parathyroid hormone (PTH): Hormone that promotes vitamin D synthesis and elevates blood calcium
paregoric: Camphorated tincture of opium used to relieve diarrhea, formerly used as a painkiller
parenchyma: Soft tissue forming the chief substance of leaves and roots, fruit pulp, and the center of stems
paroxysm: Sudden, violent spasm or convulsion; abrupt worsening of a symptom
parturient: Aiding childbirth.
passive immunity: Short-term resistance to a disease from the injection of another’s antibodies
pathogen: Any agent, particularly a microorganism, that causes disease
pathogenesis: The process by which a disease originates and develops, particularly the cellular and physiologic processes
pathogenic: Causing or producing disease.
pectin: A white, colloidal carbohydrate, found in certain ripe fruits, that has thickening properties
pedicel: Stalk of a single Hower, fruit, or leaf.
peduncle: Stalk supporting flower or flower cluster of an angiosperm or bearing the fruiting body of a fungus
pepsin: Stomach enzyme that degrades proteins.
peptic: Applied to gastric secretions and areas affected by them.
peptic ulcer: Breach in lining of the digestive tract due to excess acid, occurring in the esophagus, stomach, or duodenum
peptide: Compound of two or more amino acids.
perennial: Plant that lives more than two years, especially a herbaceous plant that produces flowers from the same root structure several years in a row
perfoliate: A leaf that appears to be perforated by the stem.
perfusion: Passage of fluid through tissue, especially blood through the lungs
peripheral resistance: Opposition to flow of blood in vessels.
peristalsis: Successive muscular contractions of the intestines, which move food through the gastrointestinal tract.
peristaltic waves: Successive contractions of tubular wall.
pessary: Vaginal appliance or medicated suppository.
petiole: The stalk of a leaf.
pH: A scale from 0 to 14 used in measuring the acidity or alkalinity of solutions. Pure water, at pH 7.0, is considered neutral. Acidity increases as the numbers decrease. Alkalinity increases as the numbers increase
pharmaceutical: A drug or medication manufactured and sold by a pharmacy
pharmacokinetic trial: A trial that studies how the drug is absorbed by the body. People in one of these trials often have blood tests every few minutes or hours
pharmacology: Medical science of drugs, which deals with their actions, properties, and characteristics.
pharmacopoeia: An official publication of drugs, in common use in a given country
pharmacy: Preparation and dispensing of drugs; place where this is done
phase I study: The first step in human testing of a drug.
Designed to evaluate: toxicity at different dose levels and takes place with a small number of participants
phase II study: drug-testing phase for effectiveness in humans. The stage in which drug effectiveness is established. Proceeds only if Phase I studies show toxicity to be within acceptable levels. Usually involves 50 to 300 volunteers
phase III study: drug-testing phase for extensive clinical trials in humans. Expansion of phase II study to 300 to 3,000 volunteers. Designed to back up information gathered in Phase I and II testing
phenol: Natural or synthetic aromatic compound containing a hydroxide (-OH) ring
pheromone: Behavioral development-mediating chemical that transmits information between individuals of the same species
phlebitis: Inflammation of a vein wall, especially in legs as a complication of varicose veins, causing extreme tenderness
phlegm: See sputum.
phospholipid: Lipid compound containing a water-soluble phosphate group
phosphorylation: The process of adding phosphate molecular groups to a compound
photosynthesis: Production of organic substances from carbon dioxide and water in green-plant cells, which chemically transform the energy of sunlight
physiological: Describes the natural biological processes of a living organism
physiology: The study of the functioning of the body, including the physical and chemical processes of its cells, tissues, organs, and systems
phytoestrogen: A plant compound that exerts estrogen-like effects
phytohormone: A plant substance that mimics the action of human hormones
phytotherapy: The treatment of disease by plants; herbal medicine
piles: See hemorrhoid.
pill: Small ball or tablet of medicine to be swallowed whole; oral contraceptive
pinnate: A leaf composed of more than three leaflets arranged in two rows along a common stalk
pituitary gland: A pea-sized structure that secretes many important hormones, located behind the hypothalamus.
placebo: (Latin: “I will satisfy.”) A medicine or preparation with no inherent pharmacologic activity
plaque: Sticky, colorless mixture of saliva, bacteria, and carbohydrates on the surface of teeth that causes tartar and caries
plasma: Fluid portion of hlood and lymph.
plaster: Pasty medicinal dressing applied to a body part on a cloth as a curative counterirritant
pleurisy: Inflammation of the pleura that cover the lungs, usually due to pneumonia or other lung disease, causing painful breathing
pneumoconiosis: Black lung.
pneumonia: Inflammation or infection of the lungs in which sacs fill with pus, causing coughing and chest pain
pneumonitis: Inflammation of the lungs.
pneumothorax: Collapsed lung.
pod: Vessel enclosing one or more seeds.
poliomyelitis: Infectious viral disease of the central nervous system, formerly epidemic, causing stiffness and paralysis of muscles, especially respiratory system muscles
pollen: Fine, dustlike grains containing male sexual cells, produced in anthers or similar structures of seed plants
polyarthritis: Inflammation of several joints at the same time.
polymer: Natural or synthetic macromolecules formed by the repetition of an identical small molecule
polymerase: An enzyme that forms long-chain polymers from simple molecular components; DNA polymerase, for example, forms DNA strands from nucleosides
polyp: Benign growth on mucous membranes especially in the nose, ear, or stomach
polypeptide: Protein, polymer of amino acid subunits.
polysaccharide: A molecule composed of many sugar molecules linked together
pomade: A prepared perfume material obtained by the enfleurage process
PPM: Parts per million.
poultice: The therapeutic application of a soft moist mass (such as fresh herbs) to the skin, to encourage local circulation and to relieve pain
prednisone: Synthetic steroid, administered orally, used to treat leukemia and Hodgkin’s disease
press: Device for orying and flattening botanical specimens.
progesterone: Hormone that prepares the uterus to receive and develop a fertilized egg
prognosis: Assessment of the future course and outcome of a patient’s disease
prophylactic: Preventive of disease or infection.
proptosis: Forward displacement of an organ, especially the eyeball
prostaglandin: Hormonelike compound manufactured from essential fatty acids
prostatitis: Inflammation of the prostate gland due to bacterial infection, sometimes causing urinary obstruction
prostration: Total exhaustion.
protease: Protein-splitting enzyme.
protein: Any of a large class of organic nitrogenous substances containing amino acids
proteinuria: Presence of protein in the urine above normal limits.
protocol: The outline or plan for use of an experimental procedure or experimental treatment
protozoa: A group of one-celled animals, a few of which cause human disease
psoriasis: Condition characterized by chronic, itchy, scaly, silvery patches of skin, especially on elbows, forearms, knees, and scalp, of unknown cause but sometimes due to anxiety
psychomotor: Relating to disorders of muscular activity affected by cerebral disturbances
pulmonary embolism: Obstruction by a blood clot in an artery that conveys blood from heart to lungs
purgative: Laxative or cathartic medication .
purpura: Skin rash due to bleeding into the skin from defective capillaries or blood platelet deficiency
pustule: Small, pus-containing blister.
putrescence: Foul smell caused by decomposition of tissue.
pyorrhea: Periodontal disease.
pyrexia: See fever.
pyrosis: See heartburn.
quinine: Alkaloid drug used to treat malaria.
quinsy: Pus-discharging inflammation of the tonsils.
radiation therapy: Treatment using X-rays, cobalt-60, radium, neutrons, or other types of cell-destroying radiation
radiosensitizer: Drug being studied to try to boost the effect of radiation therapy
randomized clinical trial: A study in which patients with similar traits, such as extent of disease, are chosen or selected by chance to be placed in separate groups that are comparing different treatments
Raynaud’s disease: Disorder, especially in women, in which spasms of arteries to extremities cause fingertips and toes to turn pale, blue, and numb
receptor: A small, chemically defined area (of a cell) that initiates a biological response upon uniting with chemically complementary areas of natural or foreign molecules
rectification: The process of redistillation applied to essential oils to rid them of certain constituents
referred pain: Pain felt in an unexpected part of the body separate from its source
reflex: Automatic, involuntary activity caused by simple nervous circuits
refrigerant: Cooling; reduces fever.
regression: The state of growing smaller or disappearing; used to describe the shrinkage or disappearance of a cancer
rejection: Immune reaction to a transplanted organ.
REM sleep: Rapid eye movement sleep.
remission: The decrease or disappearance of evidence of a disease; also, the period during which this occurs
renal calculus: Kidney stone.
renal colic: Severe pain in the kidney.
renin: A protease enzyme released by the kidney that cleaves angiotensinogen to angiotensin 1
resectable: Capable of being removed by surgery.
resin: A natural or prepared product, either solid or semisolid in nature. Natural resins are exudations from trees, such as mastic; prepared resins are oleoresins from which the essential oil has been removed
resinoid: A perfumery material prepared from natural resinous matter, such as balsam and gum resin
resolvent: An agent that disperses swelling or affects absorption of a new growth
respiration: Exchange of gases between body tissues and the surrounding environment
respiratory arrest: Cessation of breathing.
restorative: An agent that helps strengthen and revive the body systems
reticulosis: Abnormal malignant overgrowth of cells of lymphatic glands or the immune system
retrovirus: A type of virus whose genetic material consists of RNA rather than the usual DNA
rheum: Watery discharge from mucous membranes of the mouth, eyes, or nose
rheumatism: Any disorder causing aches and pains in muscles or joints
rheumatoid arthritis: Common form of arthritis that affects extremities, digits, and hips
rhinitis: Inflammation of the nasal mucosa (mucous membranes in the nasal cavities)
rhizome: Creeping horizontal stem lying at or just beneath the soil surface that bears leaves at its tip and roots from its underside
rickettsiae: Group of parasitic organisms similar to bacteria that infest the body through ticks or mites
ringworm: Highly contagious fungal infection of the skin, especially the scalp and feet or under a beard
risk: The likelihood that harm will result from exposure to a hazard
risk assessment: The process for evaluating the probability of harm resulting from a given exposure to a hazardous substance. The three steps of a risk assessment are hazard identification; dose-response assessment; and risk characterization
risk/benefit ratio: The relation between the risks and benefits of a given treatment or procedure
risk management: The regulatory decision-making process, which may take into account not only the risk assessment information, but also nonscience factors such as cost, competing public needs, technical feasibility, and societal values
root: The underground part of a plant that functions in absorption, aeration, and food storage and as a support system
rosacea: Chronic acne characterized by red, pustular lesions about the nose, cheeks, and forehead
rosette: Leaves that are closely arranged in a spiral.
rubefacient: Generating a localized increase in blood flow when applied to the skin, helping healing, cleansing, and nourishment. Often used to ease the pain and swelling of arthritic joints
saccharide: A sugar molecule.
saliva: Watery, slightly acidic secretion of salivary glands that moistens food and initiates its breakdown
salt: The chemical combination of an acid and a base yielding a salt plus water
salve: A medicinal ointment used to soothe or heal skin irritations, burns, or wounds; ointment
saponin: A glycoside that forms a soaplike lather when shaken in water. There are two broad groups: the steroidal saponins, which seem to mimic the precursors of female sex hormones, and the triterpenoid saponins, which mimic the adrenal hormone ACTH
saprophyte: A free-living organism that lives on dead or putrefying tissues
sarcolemma: The cell membrane of a muscle cell. Like the cell membrane of nerves, the sarcolemma is able to conduct action potentials
sarcoma: A tumor of connective tissue.
scab: A hard crust of blood, serum, or pus over a healing wound.
scabies: A skin infection from an infestation of mites that causes severe itching, especially around the groin and nipples and between fingers
scar: Mark left on skin by a healing wound where connective tissues replace damaged tissues; cicatrix
schistosomiasis: An intestinal disease in the tropics, due to infestation of blood flukes, that causes anemia, diarrhea, dysentery, and cirrhosis; snail fever
sciatica: Condition marked by pain down the back of the thigh, due to disintegration of an intervertebral disk, accompanied by numbness and a stiff back
sclerosis: Hardening of tissue due to inflammation.
scopolamine: A belladonna derivative.
scurvy: Vitamin C deficiency from absence of fresh fruit and vegetables in the diet that causes swollen, bleeding gums, subcutaneous bleeding, and death when prolonged
seborrhea: Excessive secretion by sebaceous glands in the face, especially at puberty; see also seborrheic dermatitis
seborrheic dermatitis: Skin eruption due to an excess secretion of sebum, common on the face at puberty
secretion: Synthesis and release of a substance by a cell or an organ
sedative: An agent that reduces functional activity; calming.
seed: Fertilized plant ovule containing the embryo, capable of germinating to produce a new plant
seizure: Sudden attack of disease or condition.
senescence: Bodily degeneration after maturity.
sepal: Leaflike, usually green, outer circle of the calyx.
septic: Affected with putrefactive destruction by disease-carrying bacteria or their toxins
septicemia: Tissue destruction by disease-causing bacteria or toxins absorbed from the bloodstream; blood poisoning
serum: Liquid portion of the blood.
sessile: Lacking a stalk.
shingles: See Herpes zoster.
sialogogue: An agent that stimulates the secretion of saliva.
side effect: A secondary and usually adverse effect, as from a drug or other treatment
soporific: A substance that induces sleep.
spasm: Sustained involuntary muscular contraction.
spasmolytic: See antispasmodic.
spastic colon: Irritable bowel syndrome.
spasticity: Resistance to passive movement of a limb; lack of motor coordination
species: Basic unit of biological classification ranking below genus, including similar organisms capable of interbreeding
splanchnic: Pertaining to the internal organs.
splenic: Relating to the spleen, the largest endocrine gland.
spondylosis: Degeneration of intervertebral disks in the backbone, causing pain and restricting movement
sputum: Mucus coughed up from the respiratory tract; phlegm.
staging: Method used to establish the extent of a patient’s disease.
standard treatment: A treatment or other intervention currently being used and considered to be of proven effectiveness on the basis of past studies
stenosis: Abnormal narrowing of a blood vessel or heart valve.
steroid: Any of the large family of chemical compounds including hormones produced by the adrenal glands, ovaries, and testes; medication used for immunosuppression and hormone replacement
STD: A sexually transmitted disease; see also venereal disease.
stimulant: An agent that quickens the physiological functions of the body
stitch: Sudden, sharp pain, usually in muscle between ribs.
stomachic: Digestive aid and tonic; improving the appetite.
stridor: Loud, harsh breathing noise due to partial obstruction of the trachea or larynx
stroke: Sudden weakness or paralysis, often on one side of the body, due to interruption of blood flow to the brain caused by thrombosis, embolus, or hemorrhage; apoplexy; cerebrovascular accident
sty: Acute bacterial infection of a gland at the base of an eyelash.
styptic: An astringent agent that stops or reduces external bleeding
subclinical: Designating suspected disease or injury that is not developed enough to produce definite signs and symptoms
subcutaneous: Giving a drug by injecting it under the skin.
submucosa: The tissue just below the mucous membrane.
succulent: Plant with thick, fleshy tissues that stores starch.
sudorific: An agent that causes sweating.
suppressor T cell: A lymphocyte controlled by the thymus gland, which suppresses the immune response
suppuration: Formation and discharge of pus.
surfactant: A compound that reduces the surface tension in water, between water and another liquid, or between a liquid and a solid
sympatholytic: A drug that affects the sympathetic nervous system
symptom: Characteristic indication of disease or disorder.
synapse: Junction between two excitable cells.
syndrome: Set of signs and symptoms indicative of a particular disease or condition
synergy: The summing of the simultaneous effects of two or more drugs such that the combined effect is greater than the effect of either of the drugs when they are given alone
systemic: Affecting the entire body, not just one part.
systole: Contraction of heart muscle.
systolic: The first number in a blood pressure reading; the pressure in the arteries during the contraction phase of the heartbeat
T cell: A white blood cell that plays an important part in the immune system. There are three types of T cells, each of which has different subsets
T-helper cell: A subset ofT cells. Physicians regularly measure T-helper cell counts in HIV-positive people. The normal range for T-helper cells is 480-1,800, but may vary
T-killer cell (cytoxic T cell): A white blood cell that kills foreign organisms after being activated by T-helper cells.
T-suppressor cell: A type of white blood cell that helps control the body’s response to an infection .
tablet: A small disk, made from compressed powders of one or more drugs, that is swallowed whole.
tachycardia: Abnormally increased heartbeat and pulse rate.
tannin: A compound that reacts with protein to produce a leatherlike coating on animal tissue (as in the process of tanning). It promotes healing and numbing (to reduce irritation), reduces inflammation, and halts infection
taproot: Deep main root from which lateral roots develop.
taxonomy: System of classifying organisms into natural related groups based on shared features or traits
tendril: Threadlike, often spiral part of climbing plant that clings to or coils around objects
teratogen: Substance that can cause birth defects.
testosterone: The principal male sex hormone produced by the testes, used in replacement therapy and as an anabolic steroid
tetany: Spasm and twitching of the muscles of the face, hands, and feet
thallus: Nonvascular plant body without clear differentiation into stems, leaves, or roots
therapeutic: Pertaining to treatment.
therapeutic index: A number, LD50/ED50, which is a measure of the approximate “safety factor” for a drug; a drug with a high index can presumably be administered with greater safety than one with a low index. The therapeutic index is ordinarily calculated from data obtained from experiments with animals
thromboembolism: Condition in which a blood clot forms at one point in circulation, dislodges, and moves to another point
thrombogenic: Causing thrombosis or coagulation of the blood
thrombosis: Formation of a thrombus or blood clot.
thrush: Whitish spots and ulcers in the mouth due to a parasite, especially in children; candidiasis
thyroid hormone (TH): Thyroxine.
tincture: An herbal remedy or perfumery material prepared in an alcohol base
tinea: Athlete’s foot.
tinnitus: Ringing in the ears.
tissue: Group of similar cells that perform a particular function.
tonic: Nurturing and enlivening.
tonsillitis: Inflammation of the tonsils due to bacterial or viral infection, causing sore throat and fever
topical: Applied directly to skin surface, not taken internally.
torpor: Sluggishness; unresponsiveness to stimuli.
toxemia: Accumulation of toxins in the blood.
toxin: Poisonous substance.
transaminase: An enzyme measurement that indicates the health of the liver
transgenic: Pertaining to the insertion by biotechnical means of a foreign gene or genes into the genetic makeup of an organism
trifoliate: A plant having three distinct leaflets.
triglyceride: Neutral fat lipid molecule composed of glycerol and three fatty acids
troche: Small, medicinal lozenge that soothes the mouth and throat
tuber: Fat underground stem from which some plants grow, similar to but shorter and thicker than a rhizome
tumescence: Swelling, especially due to the accumulation of blood or other fluid in tissue
tumor: Abnormal growth of tissue in or on a body part.
tumor necrosis factor (TNF): A protein produced by macrophages. By itself, TNF destroys cancer cells. TNF can cause fever, chills, fatigue, headache, and inflammation.
tussis: See cough.
ulcer: Open, inflamed, nonhealing sore in skin or a mucous membrane, especially in the lining of the alimentary canal.
ultrasound: A test in which sound waves are used to examine a fetus or view the internal organs.
unguent: Substance used to soothe and heal skin; ointment; salve.
urea: Nitrogenous waste product of kidneys.
uremia: The retention of urine by the body and the presence of high levels of urine components in the blood.
urethritis: Inflammation of the urethra, especially among males, due to bacterial or viral infection or obstruction.
urinalysis: The analysis of urine.
uterine: Pertaining to the uterus.
vagal: Pertaining to the vagus nerve, which supplies sensory connections to the ear, tongue, and pharynx.
vaginitis: Irritation of the vagina, due to inflammation or infection, causing burning pain and discharge.
vapors: Mentholated salve applied to chest and nose to relieve congestion.
varicella: Chicken pox.
varicose vein: Distended, sometimes painful vein in the leg, rectum, or scrotum due to obstruction of blood flow.
vasculitis: Inflammation of a blood vessel.
vasoconstriction: The constriction of blood vessels.
vasoconstrictor: An agent that causes narrowing of blood vessels.
vasodilator: An agent that dilates the blood vessels.
vector: Any agent, such as insect or tick, that transmits parasitic microorganisms and infectious diseases from host to host.
venereal disease (VD): Any infectious disease transmitted by sexual contact, now usually called sexually transmitted disease; social disease.
ventricle: One of two lower chambers of the heart.
vermicide: A chemical agent that kills parasitic worms in the intestine.
vermifuge: A chemical agent used to expel parasites from the intestine; anthelmintic.
verruca: See Wart.
vertigo: Feeling that one’s surroundings are in motion, especially spinning, due to disease of the inner ear or the vestibular nerve.
vesicant: Causing blistering to the skin; a counterirritant.
vesicle: A small blister or sac containing fluid .
vinca alkaloid: A pharmacologically active substance (e.g., vinblastine or vincristine) obtained from the genus Vinca, which includes the periwinkles.
viral load: The amount of measurable virus in the blood.
vitamin: An essential compound necessary to act as a catalyst in normal processes of the body.
volatile: Unstable, evaporates easily; see also essential oil and volatile oil.
volatile oil: A complex compound that is a chemical mixrure of hydrocarbons and alcohols in a plant.
voucher specimen: An identifiable piece of plant lodged as a specimen at an official herbarium. This is incorporated as a permanent archival specimen for furure reference and research. Archival herbaria aim for their specimens to last 400 years.
vulnerary: A remedy that promotes wound healing, especially for skin lesions and stomach ulcers.
wart: Smail, hard, benign growth in skin, caused by a virus.
welt: Raised ridge on the skin caused by a slash or a blow.
wheal: Temporary, itching, red, or pale raised area of skin due to abrasion or allergy.
xanthoma: Skin condition characterized by raised patches.
xerostomia: Diminished secretion of saliva that causes an abnormally dry mouth, especially as a drug reaction.
Hoffmann, David. Medical Herbalism : The Science and Practice of Herbal Medicine. Rochester, Vt.: Healing Arts Press, 2003.