yohimbine

yo·him·bine

noun \yō-ˈhim-ˌbēn, -bən\

Definition of YOHIMBINE

: an alkaloid obtained from the bark of yohimbe that is a weak blocker of alpha-adrenergic receptors and has been used in the form of its hydrochloride C₂₁H₂₆N₂O₃·HCl as a mydriatic and aphrodisiac and to treat male impotence—called also quebrachine