When one is engaging in doggy style sex and the female looks back, she's giving the horse eye. This is because the man can only see one of her eyes, like a horse looking at its rider.

(noun) A successful type of theft which results in an acceptable, impressive and rewarding payday for the protagonist.

To slyly check someone out by moving the eyes sharply to the side, but without moving the head.

Girl with overly spread out eyes