atropine

a poisonous crystalline alkaloid extracted from the nightshade family; used as an antispasmodic and to dilate the eye pupil; also administered in large amounts as an antidote for organophosphate nerve agents or organophosphate insecticides Also a hyponym of: poison.n.01, antidote.n.01, mydriatic.n.01, antispasmodic.n.01.