'resheath' originates from Modern English, formed from the prefix 're-' (from Latin 're-' meaning 'again') combined with the word 'sheath'.

'resheath' is derived from the verb 'sheathe' (to put into a sheath). 'Sheath' in turn comes from Old English 'sceað' (or similar spellings), and through Middle English developed into the modern word 'sheath'; the verb 'resheath' was formed in modern usage by adding the prefix 're-'.

The root 'sheath' originally referred to the protective covering itself; as a verb it meant 'to put into a sheath'. 'Resheath' later developed to mean specifically 'to put back into a sheath' (i.e., again).