poison oak

noun

either of two shrubs, Rhus toxicodendron, of the eastern United States, or R. diversiloba, of the Pacific coast of North America, resembling poison ivy and causing severe dermatitis when touched by persons sensitive to them.

poison oak

noun

either of two North American anacardiaceous shrubs, Rhus toxicodendron or R. diversiloba, that are related to the poison ivy and cause a similar rash See also sumach
not in technical use another name for poison ivy

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Word History and Origins

Origin of poison oak¹

An Americanism dating back to 1735–45

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Example Sentences

Examples have not been reviewed.

Rangers describe the trail — a steep half-mile to reach the cave, then a half-mile loop inside — as “strenuous,” featuring possible encounters with poison oak, bees, rattlesnakes and falling rocks.

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Poodle-dog isn’t a household name like poison oak and ivy, likely due to its limited geographic region and fleeting nature.

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“So we have six habitats here,” the retired family physician said, giving a dozen of us a quick warning about poison oak before breaking down the marine, plant and wildlife glories that surrounded us.

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Interesting side note: Mugwort tends to grow next to poison oak.

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That’s left firefighters toiling in poison oak with no way to get clean, he said.

From

poison ivy poisonous

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