The art of taking a poop into another persons anus. Then this person will poop it back into you, thus coming back to you like a boomerang.
Guy 1 " dude, I heard you did an Australian Boomerang last night?"
Guy 2:" Totally, except Greg had diarrhea"
Guy1 : " EWWWW"
Guy 2:" Totally, except Greg had diarrhea"
Guy1 : " EWWWW"
by Ron Bush April 4, 2008