In the theology of the Church of the SubGenius, a mystical substance or quality that is the prerequisite of all human happiness.
I read the Book of the Subgenius to find true slack in life.

"Give me liberty, or give me slack"

The CON took away all my slack.

That makes me unhappy, that's not slackfull.

Slack is the perfect hamburger...

Slack is feeling damn good, and everything goes your way.

"Slack" is a way of life.
by Doktor Agon Fly January 14, 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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gimme some space, dont nag etc

adult meanings: slacking, not working/ being active etc
teenage mother: what ya doing with that in the house, setting bad examples for little timmy here!
teenage father: gimme some slack lauren, its not that illegal
Timy: me want dope
by girl_next_door October 15, 2004
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In the context of reggae music 'slack' has to do with lyrics being lewd, vulgar or sexual.
"Dem rhymes was plenty slack"
by Ras Juan October 4, 2003
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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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Has nothing to do with "slackers" or college or hip indie movies of the nineties. Is the secret ingredient of the Universal Solvent, the Holy Grail, the true goal of all mystic beings.
"Verily I say unto thee that unto thee who haveth Slack more Slack shall be given, but whoever so should lack Slack shall lose even that." - J.R. "Bob" Dobbs
by Pope Breakfast April 5, 2003
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"I took that porno into the bathroom and slacked to it."
by Rane Tane Tane July 14, 2004
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