recoil

from The American Heritage® Dictionary of the English Language, 5th Edition.

• intransitive verb To spring back, as upon firing.
• intransitive verb To shrink back, as in fear or repugnance.
• intransitive verb To fall back; return.
• noun The backward action of a firearm upon firing.
• noun The act or state of recoiling; reaction.

from The Century Dictionary.

• To draw back; go back; retreat; take a sudden backward motion after an advance.
• To start or draw back, as from anything repulsive, distressing, alarming, or the like; shrink.
• To fall, rush, start, bound, or roll back, as in consequence of resistance which cannot be overcome by the force impressed; return after a certain strain or impetus: literally or figuratively.
• To fall off; degenerate.
• To drive back.
• To coil again.
• noun A drawing back; retreat.
• noun A backward movement; a rebound: literally or figuratively.
• noun Specifically, the rebound or resilience of a firearm or a piece of ordnance when discharged.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb obsolete To draw or go back.
• noun A starting or falling back; a rebound; a shrinking.
• noun The state or condition of having recoiled.
• noun Specifically, the reaction or rebounding of a firearm when discharged.
• noun (Gunnery) an instrument for measuring the force of the recoil of a firearm.
• noun See the Note under Escapement.
• intransitive verb To start, roll, bound, spring, or fall back; to take a reverse motion; to be driven or forced backward; to return.
• intransitive verb To draw back, as from anything repugnant, distressing, alarming, or the like; to shrink.
• intransitive verb obsolete To turn or go back; to withdraw one's self; to retire.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun firearms The amount of 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.
• verb To pull back, especially in disgust, horror or astonishment.
• verb obsolete, intransitive To retire, withdraw.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• verb come back to the originator of an action with an undesired effect
• verb spring back; spring away from an impact
• verb spring back, as from a forceful thrust
• noun the backward jerk of a gun when it is fired
• verb draw back, as with fear or pain
• noun a movement back from an impact