Hecka Dumb! Share definition Flag 1. Someone is really dumb, or lacks intellegence. 2.usually a sarcastic response to a dumb comment. 1. Arelle and Gabby, are Hecka Dumb! 2. The McBrutals are Hecka Dumb! 3. Hecka Dumb! Hecka Dumb! by Begoners March 5, 2009 0 0 Get merch Get the Hecka Dumb! mug. Buy Now — $32.95 See more merch