Synonyms of fatuous

1 Syllable

mad, dull, maer

2 Syllables

tomfool, doting, silly, sillier, simple, foolish, vacuous, loco, witless, dense, absurd, moonstruck, loopy, sappy, brainless, mindless, silliest, jerky

3 Syllables

birdbrained, inanest, insane, softheaded, puerile, lunatic, senseless, inane, idiotic, ludicrous, moronic, squirrelly

4 Syllables

boneheaded, lamebrained, schizophrenic, illogical, imbecilic, muddleheaded, imbecile, asinine, insensate