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 darkness also conceals crustaceans and other macroinvertebrates that the cavefish can prey on. —Karl Schneider, IndyStar, 17 Sep. 2025

Flamingoes were long considered to be filter feeders, passively consuming seeds, crustaceans, plant parts, and other small aquatic animals. —John Drake, Forbes.com, 16 Sep. 2025

With other biomaterials researchers are working on, such as chitosan and cellulose, a crustacean or a tree must be destroyed. —Sandy Ong, JSTOR Daily, 11 Sep. 2025

Exposure to specific proteins found in crustaceans, including shrimp, crab, and lobster—as well as mollusks such as clams, oysters, and mussels—can negatively impact the immune system. —Nick Mordowanec, MSNBC Newsweek, 11 Sep. 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