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fat·u·ous

(făch-əs)

adj.

Foolish or silly, especially in a smug or self-satisfied way: "an era of delicious, fatuous optimism shaped by the belief that enough good will on the part of people like ourselves could repair anything" (Shirley Abbott). See Synonyms at foolish.

[From Latin fatuus.]

fatu·ous·ly adv.

fatu·ous·ness n.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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