or mol·lusc

[mol-uh sk]


any invertebrate of the phylum Mollusca, typically having a calcareous shell of one, two, or more pieces that wholly or partly enclose the soft, unsegmented body, including the chitons, snails, bivalves, squids, and octopuses.

Origin of mollusk

1775–85; < French mollusque < New Latin Mollusca; see Mollusca
Related formsmol·lus·kan, mol·lus·can [muh-luhs-kuh n] /məˈlʌs kən/, adjective, nounmol·lusk·like, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for molluscs

Historical Examples of molluscs

  • At this period the best bait is small minnows, crayfish, molluscs, etc.

    Black Bass

    Charles Barker Bradford

  • The molluscs of that time had a shell more universally than those of to-day.

    Creative Evolution

    Henri Bergson

  • In this torpor the echinoderms and even the molluscs live to-day.

    Creative Evolution

    Henri Bergson

  • There were two ways in which the dye was obtained from the molluscs.

    History of Phoenicia

    George Rawlinson

  • In appearance they much resemble the young of higher species of molluscs.

    The Sea Shore

    William S. Furneaux

Word Origin and History for molluscs



1783, mollusque (modern spelling from 1839), from French mollusque, from Modern Latin Mollusca (see Mollusca), the phylum name. Related: Molluscuous; molluscan.

Online Etymology Dictionary, © 2010 Douglas Harper

molluscs in Science


Any of numerous invertebrate animals of the phylum Mollusca, usually living in water and often having a hard outer shell. They have a muscular foot, a well-developed circulatory and nervous system, and often complex eyes. Mollusks include gastropods (snails and shellfish), slugs, octopuses, squids, and the extinct ammonites. Mollusks appear in the fossil record in the early Cambrian Period, but it is not known from what group they evolved.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.