Why do we speak of the "recoil" of a rifle? Nothing in it is being re-rolled into a coil.

recoil

From Middle English recoilen from Old French reculer : re- + cul, 'buttocks' from Latin cūlus 'buttocks'. Seems to have meant to be knocked on your butt ...

Very interesting, Zmj, because it's my understanding that's exactly what happens when a rife recoils...it can send the person back on his buttocks. That origin is perfect.