Datura \Da*tu"ra\, n. [NL.; cf. Skr. dhatt?ra, Per. & Ar. tat?ra, Tat?la.] (Bot.) A genus of solanaceous plants, with large funnel-shaped flowers and a four-celled, capsular fruit. Note: The commonest species are the thorn apple ({D. stramonium}), with a prickly capsule (see Illust. of {capsule}), white flowers and green stem, and {D. tatula}, with a purplish tinge of the stem and flowers. Both are narcotic and dangerously poisonous.