The act of saying hello to one of your boys, in a douchey and frat boy type of way. Credit given to internet sensation Dom Mazzetti.
Andrew: "Yo! Waddup boosh? Hittin' the gym later?"

Pat: "Oh hell yeah bro, gotta swell out today"
by NightHawk23 January 14, 2014
Get the Waddup Boosh mug.