| eastern poison oak | (n) poisonous shrub of southeastern United States causing a rash on contact, Syn. Rhus toxicodenedron, Rhus quercifolia, Toxicodendron quercifolium |
| poison oak | (n) dermatitis resulting from contact with a poison oak plant |
| western poison oak | (n) poisonous shrub of the Pacific coast of North America that causes a rash on contact, Syn. Rhus diversiloba, Toxicodendron diversilobum |
| poison ivy | (n) climbing plant common in eastern and central United States with ternate leaves and greenish flowers followed by white berries; yields an irritating oil that causes a rash on contact, Syn. poison oak, Toxicodendron radicans, markweed, Rhus radicans, poison mercury |