Skip to Content


Pronunciation: krus-ta'she-a

Definition: 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

Disclaimer: This site is designed to offer information for general educational purposes only. The health information furnished on this site and the interactive responses are not intended to be professional advice and are not intended to replace personal consultation with a qualified physician, pharmacist, or other healthcare professional. You must always seek the advice of a professional for questions related to a disease, disease symptoms, and appropriate therapeutic treatments.
© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.