a cover that fits closely over the blade (= sharp part) of a knife or other sharp weapon or tool （刀、剑等的）鞘；（工具的）套 He put the dagger back in its sheath. 他把短剑插回鞘中。 His sword was still in its sheath. 他的剑还在鞘里。
any layer that covers and fits closely over something for protection 护套；护层；护皮 the sheath around an electric cable 电线护皮
Extra ExamplesThe wire has an outer sheath of copper. 这根电线有一层铜外壳。 The cable is protected by a strong plastic sheath. 电缆外层有结实的塑料护皮保护着。
- (British English) (also condom British and North American English, North American English or specialist prophylactic)
a thin rubber tube that a man wears over his penis during sex to stop a woman from becoming pregnant or to protect against disease 护套： 男人在性交时戴在阴茎上的一根细橡胶管，可防止妇女怀孕或预防疾病 a woman’s dress that fits the body closely 紧身连衣裙 a simple black silk sheath 简单的黑色丝绸护套
Word OriginOld English scǣth, scēath ‘scabbard’, of Germanic origin; related to Dutch schede, German Scheide, also to the verb shed.