mol·lusk also mol·lusc (mŏləsk)
Any of numerous chiefly marine invertebrates of the phylum Mollusca, typically having a soft unsegmented body, a mantle, and a protective calcareous shell, and including the snails, clams, and squids.
[French mollusque, from New Latin Mollusca, phylum name, from neuter pl. of Latin molluscus, thin-shelled, from mollis, soft; see mel-1 in the Appendix of Indo-European roots.]
mol·luscous (mə-lŭskəs) adj.
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