A man who has sex way too many times way too often. This rigorous sex causes the man to bang his jizz-bags very often, making them numb. Thus, Numb Nuts.
"Alex, you numb nut. Why did you bang HER?" OR "GODAMIT Jeff, you NUMB NUT! Why don't you go fuck a tree while you're at it?"
by Kyle-fo August 01, 2005