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

The team tethered the crustaceans to posts at varying times of the year and at varying depths of Maryland’s Rhode River, a tidal estuary in Chesapeake Bay. —Jackie Flynn Mogensen, Scientific American, 16 Mar. 2026

The team created a soft hydrogel made from chitosan, a naturally occurring polymer found in the shells of crustaceans. —Neetika Walter, Interesting Engineering, 14 Mar. 2026

These crustaceans can be harvested as early as November, but holding off until later in the season gives them more time to grow bigger and plumper. —Alana Al-Hatlani, Southern Living, 14 Mar. 2026

Removing nodules from the ocean floor disturbs the silty seabed that's home to many organisms, like worms and small crustaceans, the scientists found. —Lauren Sommer, NPR, 13 Mar. 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