Wiktionary
dumbhead
n. (context informal derogatory English) A stupid person.
Usage examples of "dumbhead".
Well, to make it plain to a dumbhead like you, we take the load and go off.
Fool around here all afternoon, maybe get some of these enlisted dumbheads drowned on us, miss the closing of the gate-how do I know the next op-order isn't waiting for us right now?
Erna Pokriefke, her legs firmly planted in our kitchen, reviled him in an amplified voice, calling him a no-good dumbhead.