The little balls of fabric that accumulate around a guy's gooch. They are usually black and come from a mixture of underwear and pubes. Gooch fuzz usually happens when you sweat alot or have really tight boxers/briefs. Sometimes gooch fuzz will cause extremely painful pube knots. They are extremely annoying and make you say wtf when they wash out in the shower.
"Dude, my mom bought me these new black boxers, and they give me the worst gooch fuzz."
"I hate gooch fuzz, the other day i had a clump of them and it knotted my ass pubes."