Synonyms of boneheaded

1 Syllable
slow, dumb, dull
2 Syllables
fatuous, dense, doltish, dopey, brainless
3 Syllables
thickskulled, dimwitted, blockheaded, ignorant, thickheaded, slow-witted, half-baked, numbskulled, dim-witted, moronic, obtuse
4 Syllables
loggerheaded
5 Syllables
insensitive