Source : Webster's Revised Unabridged Dictionary (1913)

Ulmus \Ul"mus\, n. [L., an elm.] (Bot.)
   A genus of trees including the elm.

Source : WordNet®

Ulmus
     n : type genus of family Ulmaceae; deciduous trees having simple
         serrate leaves; widely distributed in temperate regions
         [syn: {genus Ulmus}]