- Bivalve - Bivalve mollusc - Bivalve shellfish - Shellfish delicacy - Any one of many species of marine bivalve shells of the
genus Mytilus, and related genera, of the family Mytidae. The common
mussel (Mytilus edulis; see Illust. under Byssus), and the larger, or
horse, mussel (Modiola modiolus), inhabiting the shores both of Europe
and America, are edible. The former is extensively used as food in
Europe. - Any one of numerous species of Unio, and related
fresh-water genera; -- called also river mussel. See Naiad, and Unio.