| Noun | 1. | poisonberry - Eurasian herb naturalized in America having white flowers and poisonous hairy foliage and bearing black berries that are sometimes poisonous but sometimes ediblenightshade - any of numerous shrubs or herbs or vines of the genus Solanum; most are poisonous though many bear edible fruit garden huckleberry, Solanum burbankii, Solanum melanocerasum, Solanum nigrum guineese, sunberry, wonderberry - improved garden variety of black nightshade having small edible orange or black berries |