poison ivy

American  

noun

1. a vine or shrub, Rhus radicans, having trifoliate leaves and whitish berries and causing severe dermatitis when touched by persons sensitive to it.

2. poison oak.

3. the rash caused by touching poison ivy.

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poison ivy British  

noun

1. 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 contact See also sumach

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Etymology

Origin of poison ivy

An Americanism dating back to 1775–85

Example Sentences

What about snakes and ticks and poison ivy?

From The Wall Street Journal • Oct. 31, 2025

Natural healers promote oats to help soothe the skin from skin ailments including itchiness, dryness, oiliness, eczema, dermatitis, bug bites, and poison ivy.

From National Geographic • Feb. 7, 2024

Worse, most people don't know poison ivy when they see it.

From Science Daily • Jan. 30, 2024

Fire departments stretched aerial ladders over a thicket of underbrush and pine trees infested with poison ivy so officers could search from overhead.

From Washington Times • Jul. 15, 2023

If Henry had been suffering from poison ivy, hay fever, rheumatism, pinkeye, we would have been in luck but the only painkiller they had was Excedrin.

From "The Secret History" by Donna Tartt