1. (Science: botany) a plant of the genus Hedera (H. Helix), common in Europe. Its leaves are evergreen, dark, smooth, shining, and mostly five-pointed; the flowers yellowish and small; the berries black or yellow. The stem clings to walls and trees by rootlike fibres. Direct The clasping ivy where to climb. (Milton) Ye myrtles brown, with ivy never sere. (Milton) American ivy.
2. (Science: botany) An American woody creeper (rhus Toxicodendron), with trifoliate leaves, and greenish-white berries. It is exceedingly poisonous to the touch for most persons. To pipe in an ivy leaf, to console one's self as best one can. West indian ivy, a climbing plant of the genus Marcgravia.