Bro Moments can only be described as-two bros taking part in a challenging game or activity such as beer pong. When one of the two bros makes a good shot or an amazing save, you high five with each other, but instead of a small slap possibly making a small sound, you SLAM your hands together, most of the time rupturing a blood vessle in your hands and looking even more like a hard ass then normal.
Cody: *Sinks Pong Ball*
Justin: *Sinks ball in same cup*
Cody: YES! *slaps hands*
Both: OW! Bro Moment!