mollusk

noun

mol·​lusk ˈmä-ləsk How to pronounce mollusk (audio)
variants or mollusc
: any of a large phylum (Mollusca) of invertebrate animals (such as snails, clams, or squids) with a soft unsegmented body usually enclosed in a calcareous shell
broadly : shellfish
molluscan adjective
or less commonly molluskan

Examples of mollusk in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Once established, the mollusks are extremely difficult to eradicate and can damage drinking water systems, irrigation infrastructure and hydroelectric facilities while disrupting native aquatic ecosystems. Reeti Malhotra, Sacbee.com, 16 June 2026 Archaeologists have been cataloging dump sites since at least the early 19th century, when Danish scientists began pawing through heaps of mollusk shells that had been discarded by their Stone Age ancestors. Caity Weaver, The Atlantic, 12 June 2026 In the surrounding abyss, scientists have found mollusks, snails, worms, sea cucumbers, isopods, starfish and more. Harry Stevens, New York Times, 3 June 2026 That Field finds herself in this state is a low moment indeed; even the human performers in the sitcom My Mother the Car escaped with more dignity than a two-time Oscar-winning actress spilling her soul to a cephalopod mollusk. Peter Tonguette, The Washington Examiner, 30 May 2026 See All Example Sentences for mollusk

Word History

Etymology

French mollusque, from New Latin Mollusca, from Latin, neuter plural of molluscus thin-shelled (of a nut), from mollis

First Known Use

1783, in the meaning defined above

Time Traveler
The first known use of mollusk was in 1783

Cite this Entry

“Mollusk.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mollusk. Accessed 19 Jun. 2026.

Kids Definition

mollusk

noun
mol·​lusk
variants or mollusc
: any of a large phylum of invertebrate animals (as snails, clams, and octopuses) with a soft body lacking segments and usually enclosed in a shell containing calcium
molluscan adjective
also molluskan

Medical Definition

mollusk

noun
mol·​lusk
variants or mollusc
: any invertebrate animal of the phylum Mollusca
molluscan adjective
also molluskan

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