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

Previously, scientists have found tiny crustaceans, prehistoric mollusks and even hell ants encased in the orangey resin, a window into worlds past. —Sara Hashemi, Smithsonian Magazine, 23 May 2025

And one is far more likely to find fossils of algae, plants, mollusks, crustaceans, or similar smaller creatures than human remains. —Ashley Belanger – May 22, ArsTechnica, 22 May 2025

While inside the ancient Roman mine, the team noticed small crustaceans on decomposing wood chunks, the study said. —Aspen Pflughoeft, Miami Herald, 19 May 2025

As carnivores, red-lipped batfish feed on small fish, crustaceans such as shrimp and crabs, worms and mollusks, employing a sit-and-wait ambush strategy that relies on camouflage and the element of surprise. —Scott Travers, Forbes.com, 18 May 2025

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