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shellfish

American  
[shel-fish] / ˈʃɛlˌfɪʃ /

noun

  • shellfish,
    plural
  • shellfishes
    plural
  1. an aquatic animal having a shell, as the oyster and other mollusks and the lobster and other crustaceans.


shellfish British  
/ ˈʃɛlˌfɪʃ /

noun

  1. any aquatic invertebrate having a shell or shell-like carapace, esp such an animal used as human food. Examples are crustaceans such as crabs and lobsters and molluscs such as oysters

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Noun Inflected Forms

Etymology

Origin of shellfish

before 900; Middle English; Old English scilfisc. See shell, fish

Explanation

Use shellfish to refer to crustaceans and mollusks, especially the ones people commonly eat. Crabs, mussels, and shrimp are all shellfish. If you serve your guests a shellfish stew, they'll know it's full of creatures that originally had shells or hard exoskeletons. In most kitchens and restaurants, the term includes marine animals such as lobsters and oysters, and freshwater species like crayfish too. Fishery regulators only use shellfish for mollusks, including clams and mussels. The funny thing is that shellfish aren't fish at all — they're more closely related to arachnids and insects!

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Vocabulary lists containing shellfish

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:

“Duryea’s continues to be a beloved Montauk institution where families and friends come for fresh fish, shellfish, and perfect sunsets over Fort Pond Bay, as they have for decades,” a spokesman said.

From The Wall Street Journal Aug. 24, 2026

When people eat these contaminated shellfish or fish, they can get Amnesic Shellfish Poisoning, which can lead to vomiting, diarrhea, permanent short-term memory loss, coma or death.

From Los Angeles Times Jul. 29, 2026

Long periods of sea heat can trigger mass die-offs among some seagrasses, shellfish and other species, as well as encouraging greater numbers of warm-water creatures including octopus.

From BBC Jul. 7, 2026

The heat has warmed the lagoons, boosting the growth of algae that cover the shellfish.

From Barron's Jun. 27, 2026

“What’s that!” said Ron, pointing at a large dish of some sort of shellfish stew that stood beside a large steak-and-kidney pudding.

From "Harry Potter And The Goblet Of Fire" by J. K. Rowling

Here sea creatures come to live, fishes swim hungrily to and fro, and shellfishes die in the mud which, by and by, is to become firm rock with stony animal remains embedded in it.

From Eighth Reader by James Baldwin

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