crustacean

noun

crus·​ta·​cean ˌkrə-ˈstā-shən How to pronounce crustacean (audio)
: any of a large class (Crustacea) of mostly aquatic mandibulate arthropods that have a chitinous or calcareous and chitinous exoskeleton, a pair of often much modified appendages on each segment, and two pairs of antennae and that include the lobsters, shrimp, crabs, wood lice, water fleas, and barnacles
crustacean adjective

Examples of crustacean 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 lobster fries were buttery with a generous portion of the poached crustacean, plus truffle mayo, mozzarella, garlic confit and cilantro. Senior Food Editor, Los Angeles Times, 14 Apr. 2026 His harmless pre-dinner walk turns into something far whackier, sending him on a quest in a world full of giant demons and insects, magical tools and a profane crustacean. Clare Mulroy, USA Today, 11 Apr. 2026 Emperor penguins mainly consume fish, squid and crustaceans in Antarctic waters. ABC News, 9 Apr. 2026 Some groups died out, but others eventually gave rise to modern animal groups such as chordates, crustaceans and mollusks. Mindy Weisberger, CNN Money, 4 Apr. 2026 See All Example Sentences for crustacean

Word History

First Known Use

1835, in the meaning defined above

Time Traveler
The first known use of crustacean was in 1835

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Cite this Entry

“Crustacean.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/crustacean. Accessed 19 Apr. 2026.

Kids Definition

crustacean

noun
crus·​ta·​cean ˌkrəs-ˈtā-shən How to pronounce crustacean (audio)
: any of a large class of mostly water-dwelling arthropods (as lobsters, shrimps, crabs, wood lice, water fleas, and barnacles) having an exoskeleton of chitin or chitin and a compound of calcium
crustacean adjective

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