amphetamine

noun

1. a colorless, liquid drug, CHCHCH(NH)CH, that acts as a stimulant of the central nervous system and is used, usually in its crystalline sulfate or phosphate form, as a medicine to treat narcolepsy, depression, obesity, and Parkinson's disease: often used nonmedically for its stimulant effect, it is potentially habit forming
2. any closely related drug, as Dexedrine