| phylum of worms comprised of parasitic and free-living nonparasitic species |
| animal phylum comprised of sponges |
| bivalve (bī'vālv') Pronunciation Key
Any of various mollusks of the class Bivalvia, having a shell consisting of two halves hinged together. Clams, oysters, scallops, and mussels are bivalves. The class Bivalvia is also called Pelecypoda, and was formerly called Lamellibranchia. Compare univalve. |