sheath /ʃiːθ/ BrE AmE noun ( plural sheaths ) [countable]
[ Language: Old English ; Origin: sceath ]
1 . a cover for the blade of a knife or sword:
His sword was back in its sheath.
2 . British English old-fashioned a ↑ condom
3 . a protective covering that fits closely around something:
The wire is covered by an outer plastic sheath.
4 . a simple close-fitting dress:
She was wearing a plain black sheath.