noun: droopy, wrinkled, testicles that belong to a man 45 years or older. Just the thought of old man balls (more commonly referred to as O.M.B.) is enough to make you shudder with disgust.

Girl 1: "So, how is Paul in bed?"

Girl 2: "Oh man, he was turning me on and all, but then I saw his Old Man Balls (O.M.B.), and I would have needed to do some meth to get on that!"
by O.M.B. February 19, 2009
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