1. The process of playing any game in the Grand Theft Auto series for an extensive amount of time
2. Euphemism used to describe heavy spells of masturbation
3. The act of going on a total blind rage for no reason whatsoever
Klaus: "Where the hell is Hendrich going at 2:00 in the morning?"
Friederich: "Oh shit! He must be GTA-ing again."
Wolfganag: "We had better go get him."
by Ferngully3000 November 4, 2013
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