recoil

Etymology

From Old French reculer.

noun

1. A starting or falling back; a rebound; a shrinking.
   the recoil of nature, or of the blood
2. The state or condition of having recoiled.
   The recoil from formalism is skepticism. 1850, Frederick William Robertson, second address delivered to the members of the Working Men's Institute, Brighton
3. (firearms) The energy transmitted back to the shooter from a firearm which has fired. Recoil is a function of the weight of the weapon, the weight of the projectile, and the speed at which it leaves the muzzle.
4. An escapement in which, after each beat, the scape-wheel recoils slightly.

verb

1. (intransitive) To pull back, especially in disgust, horror or astonishment.
   He recoiled in disgust when he saw the mess.
2. (intransitive, now rare) To retreat before an opponent.
3. (obsolete, intransitive) To retire, withdraw.
   The solemnity of her demeanor made it impossible […] that we should recoil into our ordinary spirits. 1838, Thomas De Quincey, The Household Wreck
4. (of a firearm) To quickly push back when fired