Synonyms of lamebrain

1 Syllable

dolt, nut, kook, crank, schmuck, fool, fools, schmoes, schmo

2 Syllables

flake, crackpot, weirdo, dullard, dumdums, birdbrains, birdbrain, morons, turkey, mooncalf, screwball, airhead, thickhead, ninny, softhead, dingbat, jughead, half-wit, moron, ninnies, crazy, wacko

3 Syllables

scatterbrain, scatterbrains, simpleton, dunderhead, lunatic, fruitcake, clodpate

4 Syllables

addlepate, sociopathic