Definition of: mussel

(mus′əl) noun
1. A small bivalve mollusk, especially the common edible mussel (Mytilus edulis).
2. One of several other fresh–water mollusks, of the genera Anodonta, Unio, and others, whose shells are made into buttons, etc. ♦ Homophone: muscle. [OE musle <L musculus, dim. of mus mouse. Doublet of MUSCLE.]