What is the meaning of Mussel?

Any of several groups of bivalve shellfish with elongated, asymmetrical shells.

1. A saltwater mussel, usually edible, of the order Mytilida in subclass Pteriomorphia.
2. A freshwater mussel, usually edible, of the order Unionida in subclass Palaeoheterodonta.
3. Any of certain other bivalves of somewhat similar appearance, such as the zebra mussel and quagga mussel of the family Dreissenidae in subclass Heterodonta.

A saltwater mussel, usually edible, of the order Mytilida in subclass Pteriomorphia.

A freshwater mussel, usually edible, of the order Unionida in subclass Palaeoheterodonta.

Any of certain other bivalves of somewhat similar appearance, such as the zebra mussel and quagga mussel of the family Dreissenidae in subclass Heterodonta.

Source: wiktionary.org