A complete and utterly terrible handjob. One that is simply not worth the time and honestly makes one wonder what the fuck is wrong with with the human being who's head is in your lap.
Brady came back Jones' house and told everyone that Liz gave him the Slack-Jack of the century and he'd rather stick his dick in a pinecone than experience that again.
by SpamoniJones April 7, 2010
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The action of “jacking it” (beating the absolute fuck out of your dick) and then “slacking it “ (lying around and not doing anything
Me: When I get home I finna jack it and slack it

Random nigga: vro same that’s like all I’ve been doing lately
Me: wait who tf are you
by Inatehiggers April 18, 2018
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This is jive talking, and you shout out this when one of your homies busts a better move than you
by BILLY BILO August 3, 2005
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