noun pl \ˌkrəs-ˈtā-sh(ē-)ə\

Definition of CRUSTACEA

capitalized : a large class of mostly aquatic 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, shrimps, crabs, wood lice, water fleas, and barnacles
: arthropods of the class Crustacea
crus·ta·cean \-shən\ adjective or noun

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