Definition of mollusc in English:


(US mollusk)


  • An invertebrate of a large phylum which includes snails, slugs, mussels, and octopuses. They have a soft unsegmented body and live in aquatic or damp habitats, and most kinds have an external calcareous shell.

    • ‘As gardeners already know, all other slugs and snails (or gastropod mollusks, to the experts) sport a soft and slimy foot.’
    • ‘Small fish and a variety of other aquatic creatures, including mollusks and crustaceans, make up the Pigeon Guillemot's diet.’
    • ‘The beach sands are dominated by shells of bivalve mollusks, mainly venerids, gastropods, and echinoderms.’
    • ‘Bacteria living in the intestinal glands of a wood-boring mollusk known as the shipworm provide the animal with as much as one-third of its nitrogen.’
    • ‘Densely vegetated ditches with temporary standing water can be an important habitat for freshwater molluscs.’


Late 18th century: from modern Latin mollusca, neuter plural of Latin molluscus, from mollis soft.