8
To discharge some kind of fluid from the mouth, either phlegm, mucus or vomit.
I had a coughing fit and gacked out a lunger the size of my hand.
by amno February 13, 2003
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9
To get messed up in the process of putting the team on your back and still going out like a champ.
His night would have been better if he hadn't Gacked after the race.
by bww13 December 05, 2010
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10
Crank, lower quality methamphetamine not the higher quality crystam version but the stuff that is brown some times and burns like hell. There are 2 types of gack. One eye and two eye. One eye refers to the burning pain and tearing in the eye after snorting. Two eye gack makes both eyes burn and water from snorting it in one nostril.
"I did some gack last week and I still feel like shit!"
by PharmaPharmer December 30, 2004
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11
Uranium by product and gouda cheese mixed together to create the one and only gack. Gack has the ability to be a tasty afternoon snack or can also perform shit rockets. shit rockets will expel chunky poo from your bum at speeds exceeding 200 mph, it will, rip your rectum in half.
WOW! I ate gack last night! and it blew my ass in half!
by goo goo the magical elf November 10, 2010
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12
The first retching sound a cat makes when it hacks up a hairball.
I heard Morris gack after giving himself a tongue bath.
by the_great_waldo October 21, 2009
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13
When your girl...or guy(it is 2017)...gags on your dick
I don't care that Kaia is his girlfriend. Imma gack Dylan tonight at 12:04.
via giphy
by UpNextVanillaSwirlOnThePole March 09, 2017
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14
When you fuck your bitch so hard that her pussy makes a farting sound much like the nickelodeon puddy like material "gack"
Yo dude, last night I gacked the shit out of ashley's pussy.
by ScuryJerry January 15, 2006
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