When something is so totally good that its awesomeness can only be expressed by clenching one's fingers, turning their wrist to face the body, and dropping the elbow and shoulder in a manner that exudes awesome.

Sometimes when performing said fist pump, you should alert others to the awesome you're about to hit them with.
Guy A: Yo, did you see that girl, she's smokin... Dayumn.
Guy B: She's (*pumps fist*) FIST PUMPING GOOD, HELL YEAH!

*note how B had to alert A of the fist pumping goodness*
by David Fier August 8, 2006
Get the Fist Pumping Good mug.