A person who sucks at life. They are incapable of performing basic and simple daily tasks (with the exception of masturbation).
You have your left turn signal on and are clearly trying to merge into the left lane; instead of slowing down to allow you to change lanes, the Jackwacker behind you speeds up to block your access. This guy is a complete Jackwacker; he sucks at life.
A person who acts as if they masturbate to themselves perpetually being bigoted jackasses, so as to overcompensate for their undoubtedly small penises.
Jackwanker 1: "Hur, hur, hur, he's craaazzzeee! HUR HUR!!"
Autistic person they're pointing to, under breath: "Ugh, what an asshole."
Jackwanker 2: "Hur hur, I'm an asshole furr bein' a bigot?! Hur hur PSYCHO!"
All jackwankers: *the furious sounds of their masturbation, followed by them stinking up the place with the miniscule droplets of cum that eventually leak out the tip of their micropenises*
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.