From Longman Dictionary of Contemporary EnglishRelated topics: Biologysheathsheath /ʃiːθ/ noun (plural sheaths) [countable]1COVERa cover for the blade of a knife or sword
His sword was back in its sheath.2British English old-fashionedSY a condom3HBa protective covering that fits closely around something
The wire is covered by an outer plastic sheath.4a simpleclose-fittingdress
She was wearing a plain black sheath.Examples from the Corpussheath• The ceramics -- cablesencased in a sheath of liquidnitrogen -- are being developed for power generation and other machineryapplications.• Communications-grade fiber is measured two ways: fiber miles and sheath miles.• Here she wears number 72, a black silk crêpehoodedsheath dress and black satinshoes.• The immune system inexplicably begins attacking the protective sheathssurroundingnerves, damaging the nerves' ability to conductimpulses.• Rising hot water pulls with it a surrounding sheath of cold water, effectively insulating the base of the jet.OriginsheathOld Englishsceath
