Term used when draining a shot or making a nice layup during a basketball game.
*Daniel shooting a 3 point shot in stoner's face and making it*
Daniel: BIG FAT NUTS!
Stoner: FUCK! I just got Big Fat Nuts in my mouth
*Dwyane Wade cocking back and dunking on Perkins*
Wade: BIG FAT NUTS!
KD: Perkins just got Big Fat Nuts in his face