integument
noun
in·teg·u·ment in-ˈte-gyə-mənt 
: something that covers or encloses
especially : an enveloping layer (such as a skin, membrane, or cuticle) of an organism or one of its parts
Word History
Etymology
Latin integumentum, from integere to cover, from in- + tegere to cover — more at thatch
First Known Use
circa 1611, in the meaning defined above
Medical Definition
integument
noun
in·teg·u·ment in-ˈteg-yə-mənt
: an enveloping layer (as a skin, membrane, or husk) of an organism or one of its parts