Dead Loss
Dimwit
Dimwitted
Dingbat
Dipstick
Ditz
Donkey
Dope
Dork
Dud
Dullard
Dumb Ass
Dumb Cluck
Dumbhead
Dumbo
Dumdum
Dummy
Dunderhead
Fathead
Flake
Galoot
Goat
Goober
Goof
Goofball
Goofus
Half Baked
Halfwit
Halfwitted
Harebrained
Ill Advised
Ill Considered
Imbecile
Impolitic
Imprudent
Incautious
Informal No Hoper
Injudicious
Jughead
Klutz
Lamebrain
Lummox
Meatball
Mentally Disordered
Moron
Nincompoop
Ninny
Nitwit
Numbnuts
Numbskull
Of Unsound Mind
Pea Brained
Peabrain
Putz
Schlemiel
Schlep
Schmuck
Screwy
Simpleton
Stark Raving Mad
