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Medical Term:


Pronunciation: krus-ta'she-a


A large class of aquatic animals (phylum Arthropoda) with a chitinous exoskeleton and jointed appendages; the crab, lobster, crayfish, shrimp, isopods, ostracods, and amphipods. Some, (certain copepods), are parasitic; others serve as intermediate hosts for parasitic worms that cause disease in humans and various other vertebrates.

[L. crusta, a crust]

See Also: Copepoda

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.