Recoil means to pull back suddenly, usually because something startled, disgusted, or frightened you. When you open the refrigerator and find moldy leftovers, you might recoil in disgust. If someone reaches out to pet a dog but it barks unexpectedly, they might recoil in surprise.

The movement is instinctive and quick, like your body's automatic reaction before your brain fully processes what's happening. You recoil from a hot stove, from a spider crawling on your desk, or from an unpleasant smell. The word captures that instant, jerking-back motion.

Recoil also describes what happens when a gun fires. The explosion that launches the bullet forward creates an equal force pushing backward, making the gun kick against the person's shoulder. This is why people in movies brace themselves before firing, and why hunters practice holding their rifles steady against the recoil.

You can use recoil to describe emotional pulling back too. Someone might recoil from a mean comment or recoil at the thought of doing something unpleasant. The word suggests an immediate, visceral reaction, whether physical or emotional, not a slow, considered withdrawal.