1. A man's testicles, sperm gets made there
3. Something you yell out for no reason
Original meaning that seems to have been erased from existence: A small, spherical object used for sports
1. Jane kicked Jeff in the balls really hard.
2. He didn't have the balls to jump out the helicopter.
3. Random guy 1: "BALLS!"
Random guy 2: "....The hell is wrong with you?"