CARAPACE
carapace, shell, cuticle, shield
(noun) hard outer covering or case of certain organisms such as arthropods and turtles
Source: WordNet® 3.1
Etymology
Noun
carapace (plural carapaces)
A hard protective covering of bone or chitin, especially one which covers the dorsal portion of an animal.
in figurative use
Source: Wiktionary
Car"a*pace, n. Etym: [F.] (Zoöl.)
Definition: The thick shell or sheild which cover the back of the tortoise,
or turtle, the crab, and other crustaceous animals.
Source: Webster’s Unabridged Dictionary 1913 Edition