recoil: [13] Recoil has no connection with coil. In fact, etymologically it means virtually ‘withdraw backside first’, for it was coined in French on the basis of cul ‘arse, backside’. This went back to Latin cūlus ‘arse’, which was probably related to Sanskrit kūla- ‘rearguard’. [recoil etymology, recoil origin, 英语词源]