mollusc(n = noun.animal) mollusk, shellfish - invertebrate having a soft unsegmented body usually enclosed in a shell;
is a kind of invertebrate
has parts: carapace, cuticle, shell, shield, shellfish
is a member of mollusca, phylum mollusca
has particulars: scaphopod, gastropod, univalve, chiton, coat-of-mail shell, polyplacophore, sea cradle, bivalve, lamellibranch, pelecypod, cephalopod, cephalopod mollusk

   Same as Mollusk. [1913 Webster]

mollusc, n. (US mollusk) any invertebrate of the phylum Mollusca, with a soft body and usu. a hard shell, including limpets, snails, cuttlefish, oysters, mussels, etc.

Derivative:
molluscan adj. molluscoid adj. molluscous adj.

Etymology:
mod.L mollusca neut. pl. of L molluscus f. mollis soft