Wordnet 3.0
NOUN (1)
1. 
 deciduous monoecious nut-bearing shrubs of small trees: hazel; 
 sometimes placed in the subfamily or family Corylaceae; 
[syn: Corylus, genus Corylus]
The Collaborative International Dictionary of English v.0.48:
Corylus \Corylus\ n.
   a genus of deciduous monoecious nut-bearing shrubs or small
   trees: hazel; sometimes placed in the subfamily or family
   Corylaceae.
   Syn: genus Corylus.
        [WordNet 1.5]
WordNet (r) 3.0 (2006):
Corylus
    n 1: deciduous monoecious nut-bearing shrubs of small trees:
         hazel; sometimes placed in the subfamily or family
         Corylaceae [syn: Corylus, genus Corylus]