Any one of many species of marine bivalve shells of the genus Mytilus, and related genera, of the family Mytidæ. 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.
A saltwater shellfish that has a bluish black color shell and is a pearly color on the inside. Delicately flavored, often served steamed, broiled, or baked. Mussels are live when purchased; purchase only ones that are tightly closed. Never purchase mussels that are chipped, broken, damaged or opened. Remove store wrapping at home so that the mussels may breathe, otherwise mussels may die before they are cooked.