Australian Uppercut Share definition Flag The act of running full speed, and ramming your fist up ones ass Guy 1:See that preppy guy over there? Guy 2:Yea Guy 1I gave him an australian uppercut Australian Uppercut by SlipknotKid01 January 9, 2011 0 0 Get merch Get the Australian Uppercut mug. Buy Now — $32.95 See more merch