Slap-nuts is a modern day derogatory slur that can be used against someone who is being an idiot or suffers from severe mental-retardation. Alternatively, you can also call someone this name if they are being obnoxious and you just want them to shut the fuck up. This is the perfect term for any of the above and more!
Example:
Noah: Logan can you please not wipe me the fuck out when I'm literally about to score, we're on the same team. Fucksakes.
Logan(Slap-nuts): Then stop getting in the way mate!! Seriously, it's not hard is it?!
Dale: Logan, really man, come on. Get your head in the game and stop licking windows!
Logan: *does the exact same thing and just wipes Noah out in front of an open-goal*
Noah: For fuck sake Slap-nuts!!!! What the fuck are you doing!!! I'm about to slap my nuts on your mums coochie after this game if you keep it up!!
Technique used with the palm of the hand where one wipes his genitals, and uses the soiled hand to strike his oppenent in the facial region (Grill). Technique works best when genitals are perspiring.