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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  
/ mŏl′əsk /
  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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Nouns

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:

To avoid being eaten, the mollusk hides with its transparent body and makes a quick escape by quickly closing its oral hood, similar to the movements of a jellyfish.

From Los Angeles Times ● Nov. 14, 2024

Porosity is known to affect the structural integrity of mollusk shells, making shells weaker and potentially more susceptible to damage.

From Science Daily ● Apr. 17, 2024

The boy’s family in rural Edmond, Oklahoma, humored him with toy versions of an eight-legged mollusk, but as Cal got older it became clear that only the real thing would do.

From Seattle Times ● Apr. 15, 2024

Herman is confident that his father would be happy with his adoration for the mollusk, now chronicled in this beautiful cookbook.

From Salon ● Mar. 26, 2024

She showed Will and Lyra how to gather a particular kind of mollusk by finding their breathing tubes just above the sand.

From "The Amber Spyglass" by Philip Pullman

Trilobites scurried across the seafloor among dense clusters of shelled mollusks.

From Science Daily ● Jan. 11, 2026

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

Speaking of what makes up this most delicious and fragrant stew and despite the name, go on and include shellfish: crustaceans, mollusks or bivalves, anything you like.

From Salon ● Mar. 14, 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

Abalones are mollusks that cling tenaciously to rocks, and one has to pry them loose.

From "Long Walk to Freedom" by Nelson Mandela

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