Dermatitis resulting from contact with the poison ivy plant.
2.
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. Synonyms:markweed, poison mercury, poison oak, Rhus radicans, Toxicodendron radicans.
... found an old road which he used to travel when a boy-a road that skirted the edge of the valley, now grown up to brush, but still passable for footmen. As he ran lightly along down the beautiful path, under oaks and hickories, past masses of poison ivy, under hanging grapevines, through clumps of splendid hazelnut bushes loaded with great sticky, rough, green burrs, his heart threw off part of ... — Main-Travelled Roads • Hamlin Garland
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