sum buitch!! Share definition Flag a dirty sum buitch up the street with small balls..also called rt's (raisin testecles) often affiliated with a small brain. we pissed sum buitch off so he threw a 5 lbs barbell at my car. what a sum buitch! sum buitch!! by matt May 3, 2003 0 0 Get merch Get the sum buitch!! mug. Buy Now — $32.95 See more merch