Fatuous means lacking intelligence. When your mother outlaws calling your brother stupid, use fatuous instead.

Fatuous derives from the Latin fatuus meaning "foolish." It sounds like it should have something to do with being fat, but it actually has no relation to size. Fatuus itself comes from a root that also gave us "debate" and this might be a good way to remember it. You want to debate someone who's fatuous, because they are unintelligent, silly and even a bit conceited, so they probably won't be very persuasive debaters. Just don't call them fatuous to their face. Even if they don't know what it means, it's just not nice!

Definitions of fatuous
  1. adjective
    devoid of intelligence
    synonyms: asinine, inane, mindless, vacuous
    devoid of good sense or judgment
Commonly confused words

facetious / factious / fatuous

The word facetious describes something you don't take seriously. Remove the middle "e," and factious describes a dissenting group. And finally there's fatuous, which is a fancy way to say dumb.

Continue reading...

Word Family

Test prep from the experts

Boost your test score with programs developed by’s experts.

  • Proven methods: Learn faster, remember longer with our scientific approach.
  • Personalized plan: We customize your experience to maximize your learning.
  • Strategic studying: Focus on the words that are most crucial for success.


  • Number of words: 500+
  • Duration: 8 weeks or less
  • Time: 1 hour / week


  • Number of words: 500+
  • Duration: 10 weeks or less
  • Time: 1 hour / week


  • Number of words: 700+
  • Duration: 10 weeks
  • Time: 1 hour / week