Noun poison sumac has 2 senses
  1. poison sumac - dermatitis resulting from contact with a poison sumac plant
    --1 is a kind of
    Rhus dermatitis
  2. poison ash, poison dogwood, poison sumac, Toxicodendron vernix, Rhus vernix - smooth American swamp shrub with pinnate leaves and greenish flowers followed by greenish white berries; yields an irritating oil
    --2 is a kind of poisonous plant
    --2 is a member of Toxicodendron, genus Toxicodendron
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