Other forms: recoiled, recoils, recoiling
To recoil is to draw back suddenly in fear or disgust. Recoil in horror, recoiled from the smell, made her recoil.
It is a whole-body flinch and involuntary. In firearms, recoil is the backward push of the gun, which is momentum going the other way and is why a heavier gun kicks less. Figuratively a policy can recoil on the person who made it. Note that the French means to move back, from the word for a backside.
Old French reculer means to move backwards, from re plus cul, the backside. The English sense of flinching came from the physical movement.
Old French
reculer
English, today
recoil
From Old French reculer. Further from re- + cūlus.
Etymology from Wiktionary, CC BY-SA
Practised in Ways of Moving, Hitting & Pushing, Body Language & Gestures