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shellfish

American  
[shel-fish] / ˈʃɛlˌfɪʃ /

noun

plural

shellfish,

plural

shellfishes

  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

Etymology

Origin of shellfish

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

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.

The recalled seafood was harvested by Drayton Harbor Oyster Co. and the Lummi Indian Business Council in Drayton Harbor in Whatcom County, Wash. The contaminated shellfish was sold between Feb. 13 and March 3.

From Los Angeles Times • Mar. 10, 2026

Maryland, which has jurisdiction over the river downstream from the spill between D.C. and the Chesapeake Bay, issued an advisory for shellfish harvesting in part of the river.

From The Wall Street Journal • Feb. 19, 2026

Supriyanto, 32, is a green mussel trader and once bought from local fishermen who harvested the shellfish offshore.

From Barron's • Feb. 18, 2026

I also like to keep welcome gifts what I think of as “airplane- and pre-K–safe,” meaning I tend to avoid ingredients that aren’t allowed in those spaces, like peanuts, tree nuts and shellfish.

From Salon • Jan. 27, 2026

These shellfish inhabit the bottoms of bays and sounds and tidal rivers from New England to Texas and sheltered areas of the Pacific Coast.

From "Silent Spring" by Rachel Carson

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.