Capping a fart 

Capping a fart is the process of capturing your own fart gasses in your sealed, cupped hands. Usually followed by throwing it into the face of someone nearby.

I had had it with Jim's coy retorts, and barbed comebacks. The moment we sat down at the french restaurant, I hiked my skirt up under the table, reached down with both hands - carefully capping a fart to throw at him.

Capping a fart by A1evilboy August 18, 2009

cupping a fart 

To fart into a cupped hand and quickly bringing it up to your nose to sniff it. He cupped a fart

Joe couldn't get enough of his own farts. He sat there cupping a fart all day.

cupping a fart by McSparkorama July 26, 2006