The use of one's shirt collar, pulled up over the nose and mouth, to protect one from the stench of a recent fart. May also be pronounced "jayse" mask.
Dude, I totally just tooted. Gas masks ON.
by Irrelevant March 19, 2005
When a girl is laying on her back and you're facing her feet, you squat and teabag you're balls in her mouth and fart in her her face.
My girl spilled wine on the rug and while she was cleaning it up and I flipped her over and gave her the gas mask.
by bob and ric December 25, 2004
The act of sitting on the woman and putting a testicle on each eye and your butthole on her mouth. The man then procedes to fart in her mouth and suffocate her until death. The man then chops her up into little peices and put in a trash bag which goes in the dumpster.
Dude, i have to escape the country cuz i just gave Josie a Gas Mask.
by billy Biggsbee June 29, 2010
While receiving a blow job, just before climax, a man turns quickly and farts in a females face and spins back and cums on her face to mask in the scent
*fart noise, followed by ejaculation*
"POW! Gas Mask."
"POW! Gas Mask."
by Berkson October 04, 2008
when you capture your fart in your hand and put it on someones face
"last night i gas masked my friend. he had to smell my fart.
by holio March 04, 2008
A type of foreplay. When a male farts in a females mouth. The female then blows the fart back into the males mouth and make out.
"Oh man, I gave her a gas mask last night!"
by Freygod 2009 July 10, 2008
Where you sit on some chicks nose and fart. Then your stank ass shit blows right into that bitches lungs.
Vince gave Tracy a gas mask and she loved it! Every time vince has got to fart tracy says, take off those pants and sit on my face.
by Griz October 30, 2004