MYDRIATIC.--An agent which dilates or enlarges the pupil of the eye, whether used internally or externally, as atrophine. MYOTIC.--Any agent that contracts the pupil of the eye, whether applied to the eye or taken by the mouth, as eserine, arecoline, etc. NARCOTIC.--A medicine which produces sleep and relieves pain, but first cause cerebral excitement, as chloroform, ether, belladonna and alcohol, etc. NEPHRITIC.--A medicine used in diseases of the kidneys, as buchu, uva ursi, etc. NERVINE.--A medicine that calms nervous excitement or acts favorably in nervous diseases, as potassium bromide, chloral hydrate, etc. NUTRIENT.--A medicine which builds up the waste tissues of the system, as cod liver oil, general tonics, etc. OBTUNDENT.--Any agent which relieves irritation or reduces sensibility, as opium, poultices, etc. ODONTALGIC.--Any substance for the relief of toothache, as oil of cloves, morphine, etc. ODORANT.--Any substance with a pronounced odor, as naphthaline, asafoetida, etc. OPIATE.--A drug which causes sleep, as chloral hydrate, opium, etc. OXYTOCIC.--Any agent that produces parturition, as cotton root, ergot, etc. PANACEA.--A medicine curing all diseases; a cure all, as some patent medicines. PARASITICIDE.--A substance that destroys various animal and vegetable organisms or parasites which live upon the surface of the body, as mercurial and sulphur ointment, etc. PARTURIENT or PARTURIFACIENT.--Any agent assisting in the birth of the young, as ergot. PERISTALTIC.--A medicine which increases the movements of the longitudinal and transverse muscular fibers of the intestines and assists them in expelling their contents as nux vomica, arecoline, etc. PLACEBO.--Any medicine or inert substance given for the purpose of satisfying the patient, rather than for its medical effects, as sugar, fenugreek, anise, etc. POISON.--An agent that when introduced into the body either destroys life or impairs seriously the functions of one or more of its organs, as potassium cyanide, hydrocyanic acid, etc. POTENTIAL.--A medicine which possesses restorative effects, but is delayed in its effects, as potassium iodide, arsenic, etc. PRESERVATIVE.--A substance which prevents decomposition of another substance, as acetanilid, boric acid, etc. PREVENTIVE or PROPHYLACTIC.--A medicine or method that tends to prevent disease, as quinine for the prevention of malaria, vaccine, hygienics, etc. PROTECTIVE.--A substance used for protecting the parts to which it is applied, as collodion, etc. PUNGENT.--Any substance producing a sharp, pinching, penetrating effect, as ammonia. PURGATIVE.--A medicine causing copious evacuations of the bowels. (See Cathartics.) PUSTULANT.--A medicine which irritates and gives rise to the formation of pustules, as cantharides, croton oil, etc. RECUPERATIVE.--A medicine which restores health and energy, as extract of malt, cod liver oil, etc.