Crossword clues for the word: POISONOAK The word POISONOAK has appeared as an answer to at least 7 crossword clues on different crossword puzzles. Crossword clues for POISONOAK Showing 1 to 7 of 7 results Clue(s) Climbing plant that can cause itching It might cause a rash response? Rash cause Rash-inducing bush Rhus toxicodendron Sumac variety. Toxicodendron diversilobum