To fart into one's hand, capturing a good amount of ass gas in closed fist, and then blowing it towards it's desired target.
He hit me with his "fart dart" and I almost passed out.
To fart in one's hand and throw it at someone, as if you were throwing a dart at a target.
Jake caught me off guard with his 'buttercup,' so I threw him a 'fart dart!'
The Fart Dart
was invented at Michigan State University in January 2007 by a freshman who happened upon a golden opportunity. He captured a waft of his own silent fart
in his hand, aimed it at his roommate, and blew it into his face. Hence, the Fart Dart
Jake decided to make friends with his floor neighbors, but ruined his chances when he blew a fart dart into Justin's face.