by Cythere March 03, 2008
adj. something that has become so corroded or gummed up with a substance that it is both visbible and fairly disgusting.
by aksarah August 25, 2003
Methamphetamine (crank, speed). Describes the gag reflex triggered by the extreme burning sensation of the nasal passages when the drug is snorted, and the very bitter taste as it drains down the back of the throat.
The character 'Pooh-Bear' in the movie "The Salton Sea" had to have his nose surgically removed because he snorted too much gack.
by Anonymous July 14, 2003
by *k!nG Br@nDoN* March 09, 2005
Person: Did you know that Marilyn Manson loves gacking?
Another person: No way!!
Person: Really? Of all the things he's into, THIS, surprises you? Wow. I'm tweeting this convo, ya twat!
Another person: No way!!
Person: Really? Of all the things he's into, THIS, surprises you? Wow. I'm tweeting this convo, ya twat!
by KingFobos March 22, 2016
by mudpup April 05, 2006