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1.
the spontaneous utterance of socially objectionable or taboo words or phrases while playing a video game and to name just a few: Halo, COH, FIFA and MMORPGS

Having similarity to the most publicized Tourette Syndrome "Coprolalia", the phrases uttered by a gamer with GTS do not necessarily reflect the thoughts or opinions of the person.
While playing a video game, the gamer's character suddenly gets ambushed/attacked, dies, or was faced with something unexpected and utters an obscene words such as "F*ck! or B!tch!

Example: The house is quiet and the roommate is playing a video game while wearing his headphones so he wouldn't disturb the other people in the house

In the living room:
Gamer: (out loud) "F*******CK!!!"

At the dining table:
Non-Gamer 1 (Guest): (startled) what? what just happened?
Non-Gamer 2: "oh it's nothing, he just have Gamer's Tourette Syndrome (GTS) when he plays his video games."
by CARMC1986 November 24, 2010