- a vine or shrub, Rhus radicans, having trifoliate leaves and whitish berries and causing severe dermatitis when touched by persons sensitive to it.
- poison oak.
- the rash caused by touching poison ivy.
Origin of poison ivy
An Americanism dating back to 1775–85
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for poison ivy
She leaped to her feet and fought them wildly with her branch of poison-ivy.
The hand in which she had held the poison-ivy was beginning to itch and swell.
Poison-ivy vines often are hidden in long grass and in foliage.North Dakota
Do poison-ivy and Virginia creeper belong to the same family?A Little Garden Calendar for Boys and Girls
Albert Bigelow Paine
I'd thought of poison-ivy or some kind of plant they'd been grubbing at.Average Jones
Samuel Hopkins Adams
- any of several North American anacardiaceous shrubs or vines of the genus Rhus (or Toxicodendron), esp R. radicans, which has small green flowers and whitish berries that cause an itching rash on contactSee also sumach (def. 1)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- A North American shrub or vine that has compound leaves with three leaflets, small green flowers, and whitish berries and that causes a rash on contact.poison oak
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.