balls
n. testicles. (Potentially offensive. Use only with discretion.)He got hit right in the balls.The teacher preferred “testicles” to “balls,” if they had to be mentioned at all.
knockers
n. the testicles. (Potentially offensive. Use only with discretion.)Pow, right in the knockers. Ye gods, it hurt!He turned sideways to protect his knockers.
nuts
n. the testicles. (Potentially offensive. Use only with discretion.)Chuck got kneed in the nuts in a football game.She tried to kick him in the nuts, like she'd seen on television, but he turned too quickly.