From WordNet (r) 2.0 (August 2003) [wn]:
Fraxinus
n : ash [syn: Fraxinus, genus Fraxinus]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Fraxinus \Frax"i*nus\, prop. n. [L., the ash tree.] (Bot.)
A genus of deciduous forest trees, found in the north
temperate zone, and including the true ash trees.
[1913 Webster]
Note: Fraxinus excelsior is the European ash; {Fraxinus
Americana}, the white ash; Fraxinus sambucifolia, the
black ash or water ash.
[1913 Webster]