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
mə-ˈlə-skən How to pronounce mollusk (audio)
mä-

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.
The first tip off to the mollusk’s arrival came via a photo and a text message. — Andrew Paul, Popular Science, 8 July 2026 One of the researchers’ biggest surprises was the discovery of a particular type of shell from the mollusk Columbella rustica, too small to provide sustenance, in both the Neanderthal and Homo sapiens layers. — Katie Hunt, CNN Money, 7 July 2026 The golden mussel, a freshwater mollusk native to Southeast Asia, was first detected in North America in the Sacramento-San Joaquin Delta in October 2024. — Reeti Malhotra, Sacbee.com, 4 July 2026 On land, movements range from crawling and slithering (worms, mollusks, arthropods, snakes) to walking and running. — Literary Hub, 22 June 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

Rhymes for mollusk

See All Rhymes for mollusk

Browse Nearby Words

Molluscoidea
mollusk
Mollweide projection
See all Nearby Words

Cite this Entry

“Mollusk.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mollusk. Accessed 14 Jul. 2026.

Copy Citation

Kids Definition

mollusk

noun
mol·​lusk
variants or mollusc
ˈmäl-əsk How to pronounce mollusk (audio)
: 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
mə-ˈləs-kən How to pronounce mollusk (audio)
mä-

Medical Definition

mollusk

noun
mol·​lusk
variants or mollusc
ˈmäl-əsk How to pronounce mollusk (audio)
: any invertebrate animal of the phylum Mollusca
molluscan adjective
also molluskan
mə-ˈles-kən, mä- How to pronounce mollusk (audio)

More from Merriam-Webster on mollusk

Nglish: Translation of mollusk for Spanish Speakers

Britannica.com: Encyclopedia article about mollusk

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster

Word of the Day

Listen to the pronunciation of yaw

See Definitions and Examples »

Popular in Grammar & Usage

See More

Merriam-Webster’s Great Big List of Words You Love to Hate

Is that lie 'bald-faced' or 'bold-faced'?

'A' or 'an'? What about before 'h'? An Indefinite Article Guide

Why is '-ed' sometimes pronounced at the end of a word?

Commonly Misspelled Words
See More

Popular in Wordplay

See More

14 Phobias You Probably Haven't Heard Of

It's a Scorcher! Words for the Summer Heat

The Longest Long Words List

Ten Words Ending with a Silent ‘T’

The Words of the Week - Jul 10
See More

Popular

See More

Merriam-Webster’s Great Big List of Words You Love to Hate

14 Phobias You Probably Haven't Heard Of

It's a Scorcher! Words for the Summer Heat
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
banana-mirrored
Contradictory Words Quiz Pick out which word means one thing…and the opp...
See All