The act of one bro sucking off another bro. Typically, when one frat boy is feeling down and out for whatever reason, a male friend will be kind enough to step up and offer broral. Often perceived as a homosexual act by those who are ignorant as to the entirely non-sexual bond that two straight bros can share.
Brad: Dude, my girlfriend broke up with me. Said I spent too much time out drinking with my bros and not enough time with her.
Chad: Man, to hell with that bitch. I know what'll cheer you up. Go sit on that couch real quick.
Brad: Dude, bro, whats goi- OHHHH YEEEAAAHHH BRORAL!.
Chad: I'll even swallow to show you how tight we are. I'm not gay or anything, though.
Brad: Oh yeah, that goes without saying. Now keep sucking.