[ bahy-valv ]
/ ˈbaɪˌvælv /


Also called lamellibranch. Zoology. any mollusk, as the oyster, clam, scallop, or mussel, of the class Bivalvia, having two shells hinged together, a soft body, and lamellate gills.


Botany. having two valves, as a seedcase.
Zoology. having two shells, usually united by a hinge.
having two similar parts hinged together.


Origin of bivalve

First recorded in 1670–80; bi-1 + valve

Related forms

bi·val·vu·lar [bahy-val-vyuh-ler] /baɪˈvæl vyə lər/, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for bivalve

British Dictionary definitions for bivalve


/ (ˈbaɪˌvælv) /


Also: pelecypod, lamellibranch any marine or freshwater mollusc of the class Pelecypoda (formerly Bivalvia or Lamellibranchia), having a laterally compressed body, a shell consisting of two hinged valves, and gills for respiration. The group includes clams, cockles, oysters, and mussels


Also: pelecypod, lamellibranch of, relating to, or belonging to the Pelecypoda
Also: bivalvate (baɪˈvælveɪt) biology having or consisting of two valves or similar partsa bivalve seed capsule

Derived Forms

bivalvular, adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for bivalve


[ bīvălv′ ]

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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.