Assertion: crustacean's shell | /r/Synonym | exoskeleton
Facets:
Source sentences:
text: Most commonly crustaceans have hard shells called an exoskeleton.
text: Because they have a hard outer shell (the exoskeleton) that does not grow, they must shed their shells, a process called molting.
text: Woodlouse has tough outer shell, called exoskeleton, on the surface of the body.