Entry 1 sense Webster, 1913 Lamellibranchiate · Lam·el·li·bran·chi·ate · IPA 01 a. Having lamellar gills; belonging to the Lamellibranchia (also called Pelecypoda). 1. Having lamellar gills; belonging to the Lamellibranchia (also called Pelecypoda).(Zool.)