Definition of: drug

(drug) noun
1. Any substance, other than food, intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease in man or other animals.
2. Any article or substance recognized in the U.S. pharmacopoeia.
3. Any narcotic; also, any substance or chemical agent, exclusive of food, employed for other than medical reasons to obtain a given physiological effect or to satisfy a craving.
4. A commodity that is overabundant or in excess of demand: a drug on the market.
—v.t. drugged, drug·ging
1. To mix drugs with (food, drink, etc.), especially narcotic or poisonous drugs.
2. To administer drugs to.
3. To stupefy or poison with or as with drugs; overcome: drugged with sleep. [<MF drogue; ult. origin unknown]