1.  prickly ash(n = noun.plant) - any of a number of trees or shrubs of the genus Zanthoxylum having spiny branches;
is a kind of tree
is a member of genus zanthoxylum, zanthoxylum
has particulars: sea ash, toothache tree, zanthoxylum americanum, zanthoxylum fraxineum, hercules'-club, hercules'-clubs, hercules-club, zanthoxylum clava-herculis

2.  prickly ash(n = noun.plant) orites excelsa - Australian tree having alternate simple leaves (when young they are pinnate with prickly toothed margins) and slender axillary spikes of white flowers;
is a kind of tree
is a member of genus orites, orites

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. [1913 Webster]

2.  Hercules'-club, also called the Angelica tree. [PJC]

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