crustacean

noun

crus·​ta·​cean ˌkrə-ˈstā-shən 

: any of a large subphylum (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

Warming ocean temperatures have pushed the crustaceans south toward colder waters, which chinstraps do not tolerate. — CBS News, 7 Oct. 2026

Indeed, this celestial crustacean has no star brighter than 4th magnitude and its only claims to fame are its membership in the zodiac and beautiful M44. — Joe Rao, Space.com, 4 Oct. 2026

White lobsters are considered the rarest among the unusual color variations found in the crustaceans. — Moná Thomas, PEOPLE, 24 Sep. 2026

At the OpenClaw festival in Beijing in March, the internet-service provider Baidu set up pools with live crustaceans to entertain attendees. — Michael Schuman, The Atlantic, 19 Sep. 2026

Word History

First Known Use

1835, in the meaning defined above

Rhymes for crustacean

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

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