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mollusk

American  
[mol-uhsk] / ˈmɒl əsk /
Or mollusc

noun

  • mollusks
    plural
  1. 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.


mollusk Scientific  
/ mŏləsk /
  1. 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.


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Etymology

Origin of mollusk

1775–85; < French mollusque < New Latin Mollusca; see Mollusca

Explanation

Your pet snail, Sammy, is one example of a mollusk, or a soft, spineless animal. In Sammy's case, he has a shell, though some mollusks don't. It's a bit ironic that this term for a large phylum of invertebrates comes from a Latin word that means "soft," mollis, since many mollusks (or molluscs in Britspeak) have hard shells. The epithet comes from the nature of the creatures' bodies, whether in shell (like a snail) or without (like a slug).

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Vocabulary lists containing mollusk

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

The high presence of hearths and mollusk and fish remains in the middens suggests that the area was used for the processing and consumption of marine resources.

From Science Daily Feb. 15, 2024

The oyster farmer, Will Peckham, 31, for example, left a job in corporate finance in the city to start West Robins Oyster Co., a mollusk farm in Peconic Bay about seven years ago.

From Seattle Times Dec. 8, 2023

It wasn’t a worm, a mollusk, or a crustacean.

From Science Magazine Sep. 21, 2023

These compacted layers of mollusk fossils always amaze his students, another humble reminder that everything California is standing and building on was underwater in a previous chapter of this planet’s history.

From Los Angeles Times Aug. 22, 2023

Marie-Laure sits on a bench beside the mollusk display and trains her ears on passing groups.

From "All the Light We Cannot See" by Anthony Doerr

These included a variety of worms, mollusks, and crustaceans.

From Science Daily Nov. 2, 2025

A radioactive wasp’s nest was found at a decommissioned nuclear worksite in South Carolina, and a thriving community of tube worms and mollusks was located at the bottom of deep-sea trenches in the Pacific.

From Slate Aug. 1, 2025

The mollusks are efficient filter feeders and can increase the clarity of water by consuming large quantities of plankton, which native fish and other creatures depend on.

From Los Angeles Times Nov. 6, 2024

The so-called “hot girl food” is exactly what its name suggests: processed seafood — namely sardines, anchovies, salmon, mollusks and shellfish — that’s neatly packaged and presented in a peel-back, often decorative tin.

From Salon Oct. 11, 2024

He held out two of the black, bearded mollusks.

From "Homecoming" by Cynthia Voigt

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