An expressive hand gesture in which the individual thrusts their hand forward in a fist in front of them; traditionally extended from the chest parallel to the ground outward. At this point the individual expands the fingers, and then retracts their hand while oscillating their fingers individually upward and downward. This motion is typically used to indicate the individuals proposed ease of completion through which an action was purportedly difficult to achieve.
Jerry was so excited that his okcupid profile got 3 profile views that as he was recalling each of their names to his friends he emphasized each with an exploding fist pump.
1. The act of masturbating (the bumping of the tip of the penis) and fist pumping at the same time. This act is usually done when watching exciting porn or when someone just really likes Jersey Shore.
2. The act of making the previous definition motions as a dance.
1. Person X: Dude you wanna go down town tonight?
Person Y: Na I rented a gang bang porn and I think I'm going to cheer on the guys by doing the Head Bump, Fist Pump.
2. Person X: How are you banging a different girl every other week?
Person Y: I just Head Bump, Fist Pump like a champ at the clubs.