This is a nickname that uses reverse psychology on the classic word "Slacker" -as in to be lazy.
"Slack" is the most AWESOME word you can use to describe a person and has been developed to change expectation by subterfuge.
Dude! You are soooo Slack!!!!!!!!
by James Russell November 23, 2004
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An adjective much like chill, showing approval, contentment, or mild amusement.
Friday night was slack.
Oh man, that shot was slack!
by Fuck you October 26, 2004
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For a SubGenius, Slack can be anything you get or enjoy out of life that you don't have to work for or pay for , an approach where one stops trying to make things happen or exert control, and instead simply "allows" or "lets" favorable events to occur. Everyone is born with Original Slack, an ideosyncratic harmony with the flow of life which the unwitting Conspiracy of Normality is unceasingly trying to trick us into giving up, often as a Con-job in exchange for False Slack (anything you're sold or conned into that you have to work for or pay for, or the obligation of working or paying for it).
I just had a the most Slack-filled (week/day/hour) -- everything just fell into place and "accidentally" went my way, and I didn't have to lift a finger or pay even one red cent to make it happen that way. Hell, I even found a $20 bill, so I'm money ahead! Talk about SLACK...
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Meaning to prefer to that's disgusting and disturbing
"You slack asf for dating Bethany"
"Aye, I saw yo slack ass sister at the store"
"Yo slack ass just ate that chip up off of the floor"
by datgalmeagann January 26, 2020
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Can Refer to a female who is realy Attractive or it can refer to sex.
Wow check out that slack dude!

If she is making me take her out to dinner she better bust out the slack later man.
by Marz13 April 24, 2008
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Australian slang used alot lately showing someone not interested in doing something, or one who is lazy.
Robert: Hey lets go to the shop
Sam: Naa, slack!
by Karina September 9, 2004
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Something that is disgusting, unpleasant, and offensive to the eye.

Just down-right nasty!!

"Oh my damn"!! Why in the hell did that girl put on that!!!!! She looks so SLACK!!!

2) Lets say that some1 dose something nasty. and You say
"yo SLACK ass!!!

3) When you hear something that is Nasty. you say
"Awww that sounds Slack!!"
by Luv 2Shady December 26, 2005
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