a sheath for the blade of a sword or dagger, typically made of leather or metal (剑或匕首的)鞘 ■a sheath for a gun or other weapon or tool (武器或工具的)套
语源
Middle English: from Anglo-Norman French escalberc, from a Germanic compound of words meaning 'cut' (related to shear) and 'protect' (related to the second element of hauberk)