Synonyms of dumbbell

1 Syllable
dolt, clod
2 Syllables
dodo, dummy, saphead, dullard, dumdums, numbskull, morons, numskull, screwball, fathead, airhead, thickhead, dunce, gorked, idiot, dumbo, lame-brain, schlemiel, dumdum, jughead, barbell, dummkopf, half-wit, moron, nitwit
3 Syllables
muttonhead, simpleton, retardo, retarded, clodpate
4 Syllables
addlepate, ignoramus
5 Syllables
underachieving