bryony, (genus Bryonia), genus of about 12 species of climbing herbaceous vines in the gourd family (Cucurbitaceae). Bryony species are primarily Eurasian, though several are found in North Africa. The plants are perennials with characteristic tendrils and berries. Most species are poisonous.
Cretan bryony (Bryonia cretica) has a thick fleshy white root, large lobed leaves, pale yellow flowers arranged in clusters in the leaf axils, and small red fruits. The plant was formerly used as a cathartic and as a diuretic and contains the poisonous alkaloid bryonin. White bryony (B. alba) differs from Cretan bryony in having male and female flowers on the same plant and black berries.
The unrelated black bryony (Tamus communis, or Dioscorea communis) is a European perennial vine with yellow flowers and poisonous fruits and tubers. It is a member of the yam family (Dioscoreaceae).