'Unio' definitions:
Definition of 'Unio'
From: WordNet
noun
Type genus of the family Unionidae [syn: Unio, genus Unio]
Definition of 'Unio'
From: GCIDE
- Unio \U"ni*o\, n. [NL., fr. L. unio unity, union, a single large pearl. See Union.] (Zool.) Any one of numerous species of fresh-water mussels belonging to Unio and many allied genera. [1913 Webster]