• Poison-ivy

    Full definition of poison-ivy

    Noun

    poison-ivy

    (uncountable)
    (Toxicodendron radicans or Rhus toxicodendron)
    1. A woody vine plant in the family Anacardiaceae well-known for its ability to produce urushiol, a skin irritant that causes an itching rash for most people.

    Usage notes

    Although usually written as poison ivy, the name is often spelled "poison-ivy" to indicate that it is not a true Ivy or Hedera.

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