poison ivy

noun

1

a

: a climbing plant (Toxicodendron radicans synonym Rhus radicans) of the cashew family that is especially common in the eastern and central U.S., that has ternate leaves, greenish flowers, and white berries, and that produces an irritating oil causing a usually intensely itching skin rash

b

: any of several plants closely related to poison ivy

2

: a skin rash caused by poison ivy

Illustration of poison ivy

• poison ivy 1a

Examples of poison ivy in a Sentence

I got poison ivy all over my arm.

Recent Examples on the Web

Itching and stinging: Breast milk has been used on the skin to relieve the sting and itching of insect bites, bee stings, chicken pox, poison ivy, poison oak, and poison sumac. —Donna Murray, Rn, Parents, 29 July 2024

Take your camera and watch out for poison ivy nearby. —Margot Mazur, Travel + Leisure, 28 July 2024

Summary Calamine lotion is a topical OTC remedy for itching and irritation associated with skin conditions like poison ivy, bug bites, and allergic reactions. —Megan Nunn, Pharmd, Verywell Health, 26 July 2024

Here's how to tell poison ivy from look-alike plants. —Andy Wilcox, Better Homes & Gardens, 25 July 2024

Word History

First Known Use

1782, in the meaning defined at sense 1a

Kids Definition

poison ivy

noun

1

: a usually climbing plant that is related to the sumacs, has leaves usually with three leaflets, greenish flowers, white berries, and leaves and stems that when bruised and touched may cause an itching rash on the skin

2

: a skin rash caused by poison ivy

Medical Definition

poison ivy

noun

-ˈī-vē 

1

a

: a climbing plant of the genus Rhus (R. radicans synonym Toxicodendron radicans) that is especially common in the eastern and central United States, that has leaves in groups of three, greenish flowers, and white berries, and that produces an acutely irritating oil causing a usually intensely itching skin rash

b

: any of several plants closely related to poison ivy

especially : poison oak sense 1b

2

: a skin rash produced by poison ivy