crustacean

American  

[kruh-stey-shuhn] / krʌˈsteɪ ʃən /

noun

1. any chiefly aquatic arthropod of the class Crustacea, typically having the body covered with a hard shell or crust, including the lobsters, shrimps, crabs, barnacles, and wood lice.

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adjective

1. belonging or pertaining to the crustaceans.

crustacean British  

/ krʌˈsteɪʃən /

noun

1. any arthropod of the mainly aquatic class Crustacea, typically having a carapace hardened with lime and including the lobsters, crabs, shrimps, woodlice, barnacles, copepods, and water fleas

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adjective

1. of, relating to, or belonging to the Crustacea

crustacean Scientific  

/ krŭ-stā′shən /

1. Any of various widespread arthropods of the class Crustacea that live mostly in water and have a hard shell, a segmented body, and jointed appendages. Crustaceans include crabs, lobsters, shrimp, barnacles, and copepods.

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crustacean Cultural  

1. A class of arthropods with shells.

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Discover More

Crabs, lobsters, shrimp, and crayfish are crustaceans.

Etymology

Origin of crustacean

1825–35; < New Latin Crustace ( a ) (neuter plural) hard-shelled ones ( see crust, -acea) + -an

Explanation

A crustacean is a member of a class of arthropods that live in water. Some of your favorite seafood comes from crustaceans — crabs, lobsters, and shrimp. There are plenty of fish in the sea, and there are also plenty of crustaceans: strange-looking aquatic critters who usually have at least four pairs of limbs, plus a segmented body and a chitinous exoskeleton. If you think of a crust as being a little like a shell, that can help you remember crustaceans are essentially critters that have shells. Our word crust is from Latin crusta (shell or crust).

Example Sentences

Crustacean specialist Pipit Pitriana from Indonesia's National Research and Innovation Agency is fascinated by the captured lobster, as well as some pearl-sized barnacles she thinks may be new to science.

From Barron's • Jan. 26, 2026

Several thousand records were sourced on-campus from the Crustacean Collection of the Illinois Natural History Survey, part of the Prairie Research Institute at Illinois.

From Science Daily • Nov. 25, 2024

Crustacean enthusiasts among you will have noticed that we have used the term shrimp throughout this piece.

From BBC • Feb. 23, 2023

Ms. Teigen had been trying out the tasting menu of Crustacean, a Vietnamese restaurant in Beverly Hills, and sat alone in a booth with her large bow.

From New York Times • Mar. 24, 2021

Before the boats were out of sight of the still stranded Crustacean two sea-planes ascended and flew swiftly inland.

From Rounding up the Raider A Naval Story of the Great War by Westerman, Percy F. (Percy Francis)

Related Words

• shellfish