crustacean

noun

crus·​ta·​cean ˌkrə-ˈstā-shən 

: 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

Their diet is the most diverse of any of the smaller whales, eating over 100 species of marine and freshwater fish, mollusks, crustaceans, and zooplankton. —Kelsey Monstrola, USA Today, 17 Apr. 2026

Scientists say this indicates that the medicines were muting the crustaceans' pain processing. —Christopher Edwards, PEOPLE, 17 Apr. 2026

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

Emperor penguins mainly consume fish, squid and crustaceans in Antarctic waters. —ABC News, 9 Apr. 2026

Word History

First Known Use

1835, in the meaning defined above

Rhymes for crustacean

• ablation
• bination
• carnation
• cassation
• castration
• causation
• centration
• cessation
• cetacean
• chelation
• citation
• collation

Kids Definition

crustacean

noun

crus·​ta·​cean ˌkrəs-ˈtā-shən 

: 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