look up any word, like bukkake:
 
1.
Where a guy is driving down the road and the girl decides she doesn't like what he just told her, so she threatens to NUT PUNCH him in the balls. This can only be accomplished while the guy is driving and not standing up.
While Kasey and Dale were driving down the road, Dale made a smartass comment and was nut punched by Kasey.
by Infinite Reality May 27, 2009
 
2.
A punch to the testicles. Often causes immense pain/temporay paralysis/sterility. Most often debilitating.
Steak:I tried to kiss my girlfriend during that time of month and she gave me a debilitating nutpunch.
by Xarionis aka Omnivore December 13, 2003