stump dumb Share definition Flag The dumbest of all the dumbs possible. Dumb as a stump, or a bump on a log. Often used in reference to rednecks. My neighbors are stump dumb hillbilly redneck neandertals. stump dumb by mangus May 25, 2004 0 0 Get merch Get the stump dumb mug. Buy Now — $32.95 See more merch