Simple Definition of crustacean

from our Learner's Dictionary

crustacean

noun

krəˈsteɪʃən

plural crustaceans

technical : a type of animal (such as a crab or lobster) that has several pairs of legs and a body made up of sections that are covered in a hard outer shell

Note: Crustaceans usually live in the water.

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“Crustacean.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/crustacean. Accessed 18 Jun. 2026.

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Simple Definition of crustacean

crustacean

noun

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