lamellibranch

from WordNet (r) 3.0 (2006)

lamellibranch
    adj 1: bivalve [syn: {lamellibranch}, {pelecypod},
           {pelecypodous}]
    n 1: marine or freshwater mollusks having a soft body with
         platelike gills enclosed within two shells hinged together
         [syn: {bivalve}, {pelecypod}, {lamellibranch}]

from The Collaborative International Dictionary of English v.0.48

Lamellibranch \La*mel"li*branch\, n. (Zool.)
   One of the Lamellibranchia (also called Pelecypoda). Also
   used adjectively.
   [1913 Webster] Lamellibranchia

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