poison ivypoison ivy
- any of several woody vines or shrubs (genus Rhus, esp. R. radicans), of the cashew family, having leaves of three leaflets, greenish flowers, and ivory-colored berries: it can cause a severe rash on contact
- a rash or dermatitis so caused
- A North American shrub or vine (Toxicodendron radicans) that has compound leaves with three leaflets, small green flowers, and whitish berries and that causes a rash on contact.
- A skin rash caused by contact with this plant. In both senses also called poison oak.
(uncountable) (Toxicodendron radicans or Rhus toxicodendron)