something that really sucks.

also a quote from a vine where a black man just yells
his hair? WACK
his gear? WACK
his jewelry? WACK
his foot stance? WACK
the way he talks? WACK
the way he doesn’t even like to smile? WACK
me? I ‘ M T I G H T A S F U C K
by olivaègay November 28, 2018
an adjective used to refer to something crazy, weird, and/or unbelievable
Amir: Yo, did you see mr. brown break dancing in his cow costume?
Zach: Yeah, that was wack bro
by ur b1tch November 22, 2019
1. To be of low or dubious quality. Origin: comes from 'whacky', which evolved to 'whacked' or 'whacked out'. Eventually shortened to 'wack'. The 'h' is usually dropped to differentiate the meaning from 'whack', which is to hit something hard or, kill (old wise guy terminology).
Yo, my dog, those shoes are wack.
by Paul October 13, 2004
1) Lame, sorry ass, aint even legit

2) To Jerk off
Example 1:

Tracy: I'm all that and a bag of chips!..and then some!

Rob: Shut yo wack ass up!.. and gets off my Grill.

Example 2:

Tracy: What did u do last night?

Rob: I was wacking my dick ...RAW... thinking about you.
by Shady Ass Rob February 5, 2003
something that sucks horribly; stupid; fake; talentless
that new jay-z joint is wack as fuck.
by zach November 25, 2002
When you commentating a ping-pong ball match
Guy 1: hits ping pong ball
Guy 2: hits ping pong ball
You, the commentator: wack wack wack wack wack wack
by foop629 August 18, 2019
Wack - crap, shitty, no good.

A word used verbally by those who see themselves and their peers as gangster.
For someone to define something as wack, theyre saying its shit.
Person 1: Yo, you want a drag of this?
Person 2: Nah that shit is wack.
by Giorgio Enziano April 20, 2008