amphetamine, pep pill, upper, speed - a central nervous system stimulant that increases energy and decreases appetite; used to treat narcolepsy and some forms of depression

barbiturate - organic compound having powerful soporific effect; overdose can be fatal

drug - a substance that is used as a medicine or narcotic

gateway drug - a habit-forming drug that is not addictive but its use may lead to the use of other addictive drugs; "one college athlete recently called beer a gateway drug for young people"

LSD, lysergic acid diethylamide - a powerful hallucinogenic drug manufactured from lysergic acid

depressant, downer, sedative, sedative drug - a drug that reduces excitability and calms a person

soft drug - a drug of abuse that is considered relatively mild

baccy, tobacco - leaves of the tobacco plant dried and prepared for smoking or ingestion

alcohol, alcoholic beverage, inebriant, intoxicant - a liquor or brew containing alcohol as the active agent; "alcohol (or drink) ruined him"