Technical term for physical recoil, such as the backward movement of a firearm upon firing.
When you fire a gun, the recoil is transmitted to your shoulder.
recoil atom
Compound of 反 (はん, 'anti-; opposite') and 跳 (ちょう, 'jump; spring'), literally 'reverse spring'. The exact historical derivation is uncertain, but the spelling is conventionally associated with the meaning of recoil.