Prickly ash Bot.,
  1.  A prickly shrub (Xanthoxylum Americanum) with yellowish flowers appearing with the leaves; also called toothache tree. All parts of the plant are pungent and aromatic.  The southern species is Xanthoxylum Carolinianum. --Gray.
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  Xan·thox·y·lum n.  Bot. A genus of prickly shrubs or small trees, the bark and rots of which are of a deep yellow color; prickly ash.
  Note: ☞ The commonest species in the Northern United States is Xanthoxylum Americanum.  See Prickly ash, under Prickly.
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