noun \ˈyünēˌō\

Definition of unio

  1. 1 capitalized :  the type genus of the family Unionidae comprising freshwater mussels that have an oblong shell pearly within and covered without by a greenish or blackish epidermis

  2. 2 plural unios \-ōz\ or unionides :  any mussel of Unio or a related genus



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Origin and Etymology of unio

New Latin, from Latin, a large pearl — more at 3union

Seen and Heard

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capable of being understood in two ways

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