When put in a situation where one must release intestinal gas in a group surrounding, said person makes a fake fart noise with the hand on the mouth just as the fart is released. The trickery comes in all the people around you thinking the fart was fake, while in actuality there was a dual fart noise they could not pick up on.
"When Steve pulled a fartfinagle on the girls, it was so believable that they thought he made it smell so bad using his hand."
by Jeff Greenberg October 17, 2003