Someone who is crazy and/or has lost their mind and acts like a damn lunatic. Someone you should avoid at all costs as they may be a harm to yourself or others.
Let's cross the street. We don't want to walk next to that wack job on the corner who's walking in circles and talking to himself.
ayon kay Phoebe Beaver ika-04 ng Agosto, 2005
A spastic, nerdy, and repressed professional who attends the office early.
What the fuck wackjob, what are you doing here at 700AM, you shit the bed!?!
ayon kay ian l wachowicz ika-04 ng Oktubre, 2006
A really bad blow-job.
I got my girlfriend to go down on me, but I think she didn't know what she was doing because she gave me a wack-job!
ayon kay mandythewombat ika-26 ng Abril, 2015
a complete nut absolutly fucking crazy some syn. mother-in-law, nut, loon etc.
That girl is total fucking wackjob.
ayon kay april hussler ika-20 ng Marso, 2004
An idiot; a loser; another term for jerkoff.
That guy is such a wack job.
ayon kay Emby Quinn ika-22 ng Oktubre, 2003
A crazy person, but not in the good or cool kinda way, they constantly do stupid stuff and say stupid things and no one understands them, they usually can't get a girlfriend(or boyfriend, depending on the gender or sexuality) and can really get on your nerves.
Jordan kept bugging me, he kept poking me and yelling me 'anime walruses lurk in your watermelon potato salad' and he kept trying to lick my friend, for he is a freaking wackjob.
ayon kay AGuyWhoLikesNachos ika-08 ng Hunyo, 2013
to masturbate, or give pleasure to one's self. Mostly used to describe male masturbation (jack off) but can still be used for female pleasuring.
'Dude why is Riley taking so long?' 'he's giving himself a wack job'
ayon kay smartblondeawsomeperson;) ika-01 ng Pebrero, 2010