Definition of: lamellibranch

(lə·mel′i·brangk) noun
One of a class (Pelecypoda, formerly Lamellibranchiata) of mollusks, having bivalve shells enclosing a mantle within which is the compressed body of the organism, including clams, mussels, and oysters.
—adjective Of or pertaining to this class. [<NL lamellibranchia, name of this class <L lamella LAMELLA + Gk. branchia gills, plural of branchion a fin]
—la·mel′li·bran′·chi·ate (-brang′kē·āt, -it) adjective & noun