- a poisonous plant, Atropa belladonna, of the nightshade family, having purplish-red flowers and black berries.
- a drug from the leaves and root of this plant, containing atropine and related alkaloids: used in medicine to check secretions and spasms, to relieve pain or dizziness, and as a cardiac and respiratory stimulant.
- either of two alkaloid drugs, atropine or hyoscyamine, obtained from the leaves and roots of the deadly nightshade
- another name for deadly nightshade
