A Sheath

1. A holster for a sword; a scabbard.
2. (by extension) Anything that has a similar shape to a scabbard that is used to hold an object that is longer than it is wide. Synonyms: case, casing, cover, covering, envelope
3. (botany) The base of a leaf when sheathing or investing a branch or stem, as in grasses.
4. (electrical engineering) The insulating outer cover of an electrical cable.
5. (entomology) One of the elytra of an insect.
6. (fashion) A tight-fitting dress.
7. (zoology) The foreskin of certain animals (for example, dogs and horses).
8. (Britain, informal) A condom.Synonyms: see Thesaurus:condom