The act of being wacked in the testicles by someone with a forcable back hander.

Briefly, "the realization that each random passerby is living a life as vivid and complex as your own." Originally from the Dictionary of Obscure Sorrows, which has a lot more beautiful neologism definitions like this you might enjoy.

To hit someone in the balls with the back of your hand generating power from a backswing of the stronger arm and finishing with a graceful flick of the wrist...
- From the Ancient Roman word 'sackuswakus' - meaning 'ruptured ballsack'

1) where your use torque in your wrist to whip someones area where their lower genitals are

2) Sack wack can also be a technicial name for the process in which homosexuals use the back of their hand to slap someones ball bag (nut sack).

3)can also be a sport

Masturbating in bed.

When you flick the ball sack of your mate with a downward flick of your hand using the tips of the fingers.

Same as sack tap

Aka when you hit your bro in the dick then run away so that you can still have kids