butt pebble Share definition Flag (When you have large load to drop in the toilet) what the "large load" splits into, usually the size of pea gravel or marbles. d00d i counted 50 butt pebbles in there.... butt pebble by drkratchet105 June 18, 2008 0 0 Get merch Get the butt pebble mug. Buy Now — $32.95 See more merch