The rare occurrence when one simultaneously burps and farts at the same time. An extremely relieving but somewhat embarrassing event. Men are usually impressed while women are usually disgusted, but secretly impressed.
Norm: Dude, i really really regret eating at taco bell last night. what were we thinking?
Steve: Yeah I was multi gassing until 3 am.
Norm: Awesome.
Steve: Yeah I was multi gassing until 3 am.
Norm: Awesome.
by footballchamp834 August 20, 2008