wrapper

Short definition from Wiktionary

Noun

1. 1
   Something that is wrapped around something else as a cover or protection: a wrapping.
2. 2
   An outer garment; a loose robe or dressing gown.
3. 3
   One who, or that which, wraps.
4. 4
   A construct, such as a class or module, that serves to mediate access to another.
5. 5
   A startup company that sells technology that it largely does not make.