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mol·lusk also mol·lusc

(mŏləsk)

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·luscous (mə-lŭskəs) adj.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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