There are many words used to describe herbs and their actions on the body. The following is a guide to understanding these unique terms.

Adaptogen
a substance that invigorates or strengthens the system (also called a tonic).

Alterative
a substance that produces a gradual, beneficial change in the body.

Alkaloid
heterogeneous group of alkaline, organic, compounds containing nitrogen and usually oxygen; generally colorless and bitter-tasting; especially found in seed plants.

Analgesic
a substance that reduces or relieves pain.

Anodyne
a pain relieving agent, less potent than an anesthetic or narcotic.

Antihelmintic, anthelmintic
a substance that expels or destroys intestinal worms (also called a vermifuge).

Antihydrotic
a substance that reduces or suppresses perspiration.

Antipyretic
an agent that reduces or prevents fever (also called a febrifuge).

Antispasmodic
an agent that relieves spasms or cramps.

Aperient
a mild and gentle-acting laxative.

Aperitif
an agent that stimulates the appetite.

Aphrodisiac
a substance that increases sexual desire or potency.

Aromatic
a substance with a strong, volatile, fragrant aroma; often with stimulant properties.

Astringent
an agent that contracts or shrinks tissues; it is used to decrease secretions or control bleeding.

Bitter tonic
a substance with an acrid, astringent or disagreeable taste that stimulates flow of saliva and gastric juices.

Bolus
a suppository poultice used for vaginal or rectal application; made by mixing powdered herb material in melted cocoa butter or similar base and hand-forming suppositories as the matrix cools.

Calmative
an agent with mild sedative or hypnotic properties.

Carminative
a substance that stops the formation of intestinal gas and helps expel gas that has already formed.

Catarrh
inflammation of a mucous membrane, especially of the respiratory tract.

Cathartic
a powerful agent used to relieve severe constipation (also called a purgative).

Cholegogue
an agent that stimulates secretion and release of bile.

Choleretic
an agent that stimulates the formation of bile.

Concentration
the amount of material in a solution in relationship to the amount of solvent; expressed as the ratio.

For example:

• 1:5 concentration means that 5 parts of an extract contains the equivalent of one part of the raw herb;
• 4:1 concentration means that 1 part of an extract contains the equivalent of 4 parts of the raw herb.

Counterirritant
an agent that causes a distracting irritation intended to relieve another irritation.

Decoction
extract of a crude drug made by boiling or simmering (cooking) herbs in water; stronger than a tea or infusion.

Demulcent
an oily or mucilaginous substance that soothes irritated tissue, especially mucous membranes.

Diaphoretic
an agent, taken internally to promote sweating (also called sudorific).

Diuretic
an agent that promotes urine production and flow.

Emetic
a substance that induces vomiting.

Emmenogogue
an agent, taken internally, to promote menstrual flow.

Emollient
an externally applied agent that softens or soothes skin.

Essential oil
any of a class of volatile oils that impart the characteristic odors of plants; used especially in perfumes, food flavorings and aromatherapy; also called volatile oil.

Expectorant
an agent that increases bronchial secretions and facilitates their expulsion through coughing, spitting or sneezing.

Extract
a concentrate, made by steeping raw plant material(s) in solvent (alcohol and/or water), after which the solvent is allowed to evaporate.

Febrifuge
an agent that reduces fever (also called an antipyretic).

Flatulence
gas in the stomach or intestines.

Fluid extract
a liquid extract of raw plant material(s), usually of a concentration ratio of 1 part raw herb to 1 part solvent (1:1).

Fomentation
application of a warm and moist cloth, soaked in an infusion or decoction, as treatment.

Galactogogue
an agent that increases secretion of milk (synonym for lactagogue).

Galenical
herb and other vegetable drugs as distinguished from mineral or chemical remedies; crude drugs and the tinctures, decoctions, and other preparations made from them, as distinguished from the alkaloids and other active principles.

Glycoside
esters containing a sugar component (glycol) and a nonsugar (aglycone) component attached via oxygen or nitrogen bond; hydrolysis of a glycoside yields one or more sugars.

Hemostatic
an agent used to stop internal bleeding.

Herb
plant or part of a plant used for medicinal, taste or aromatic purposes.

Humectant
a substance used to obtain a moistening effect.

Hygroscopic
a substance that readily attracts and retains water.

Infusion
tea made by steeping herb(s) in hot water.

Lactagogue
an agent that increases secretion of milk (synonym for galactogogue).

Laxative
a substance that promotes bowel movements.

Maceration
a process of softening tissues by soaking in liquid.

Mucilage
a gelatinous substance, containing proteins and polysaccharides, that soothes inflammation.

Mucilaginous
an agent characterized by a gummy or gelatinous consistency.

Nervine
an agent that calms nervousness, tension or excitement.

Oleoresin
a homogenous mixture of resin(s) and volatile oil(s).

Pharmacognosy
the study of the biochemistry and pharmacology of plant drugs, herbs, and spices.

Phlogistic
referring to inflammation or fever.

Poultice
a soft, moist mass applied to the skin to provide heat and moisture.

Purgative
a powerful agent used to relieve severe constipation (also called a cathartic).

Raw herb
the form of the plant, or plant parts, unchanged by processing other than separation of parts, drying or grinding.

Resin
any of several solid or semi-solid, flammable, natural organic substances soluble in organic solvents and not water; commonly formed in plant secretions; complex chemical mixtures of acrid resins, resin alcohols, resinol, tannols, esters, and resenes.

Rubefacient
an agent, applied to the skin, causing a local irritation and redness; for relief of internal pain.

Salve
an herbal preparation mixed in oil and thickened with bees wax applied to the skin.

Saponin
any of several surfactant glycosides that produce a soapy lather; found in plants.

Sedative
a substance that reduces nervous tension; usually stronger than a calmative.

Sialogogue
an agent that stimulates secretion of saliva.

Solid extract
an extract of plant material(s) made by removing the solvent from a fluid extract.

Soporific
a substance that induces sleep.

Stimulant
an agent that excites or quickens a process or activity of the body.

Stomachic
an agent that gives strength and tone to the stomach or stimulates the appetite by promoting digestive secretions.

Styptic
a substance that stops external bleeding (usually an astringent).

Sudorific
an agent, taken internally, to promote sweating (also called diaphoretic).

Tannin
a complex mixture of polyphenols; gives a color reaction to iron-containing substances.

Terpene
any of several isomeric hydrocarbons; most volatile oils consist primarily of terpenes.

Tincture
a solution prepared by steeping or soaking (maceration) plant materials in alcohol and water.

Tonic
a substance that invigorates or strengthens the system (also called adaptogen); tonics often act as stimulants or aleratives.

Vermifuge
a substance that expels or destroys intestinal worms (also called antihelmintic or anthelmintic).

Volatile oil
an odorous plant oil that evaporates readily; also called essential oil.

Vulnerary
a substance used in the treatment or healing of wounds.