id·​i·​ot | \ ˈi-dē-ət \

Definition of idiot

1 : a foolish or stupid person
2 dated, now offensive : a person affected with extreme mental retardation

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Other Words from idiot

idiot adjective

Synonyms & Antonyms for idiot


airhead, birdbrain, blockhead, bonehead, bubblehead, chowderhead, chucklehead, clodpoll (or clodpole), clot [British], cluck, clunk, cretin, cuddy (or cuddie) [British dialect], deadhead, dim bulb [slang], dimwit, dip, dodo, dolt, donkey, doofus [slang], dope, dork [slang], dullard, dumbbell, dumbhead, dum-dum, dummkopf, dummy, dunce, dunderhead, fathead, gander, golem, goof, goon, half-wit, hammerhead, hardhead, ignoramus, imbecile, jackass, know-nothing, knucklehead, lamebrain, loggerhead [chiefly dialect], loon, lump, lunkhead, meathead, mome [archaic], moron, mug [chiefly British], mutt, natural, nimrod [slang], nincompoop, ninny, ninnyhammer, nit [chiefly British], nitwit, noddy, noodle, numskull (or numbskull), oaf, pinhead, prat [British], ratbag [chiefly Australian], saphead, schlub (also shlub) [slang], schnook [slang], simpleton, stock, stupe, stupid, thickhead, turkey, woodenhead, yahoo, yo-yo


brain, genius

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Idiot Has Greek Roots

The Greek adjective idios means “one’s own” or “private.” The derivative noun idiōtēs means “private person.” A Greek idiōtēs was a person who was not in the public eye, who held no public office. From this came the sense “common man,” and later “ignorant person”—a natural extension, for the common people of ancient Greece were not, in general, particularly learned. The English idiot originally meant “ignorant person,” but the more usual reference now is to a person who lacks basic intelligence or common sense rather than education.

Examples of idiot in a Sentence

Don't be such an idiot! only an idiot would invest in a company just because a casual acquaintance recommended it

First Known Use of idiot

14th century, in the meaning defined at sense 2

History and Etymology for idiot

Middle English, from Anglo-French ydiote, from Latin idiota ignorant person, from Greek idiōtēs one in a private station, layman, ignorant person, from idios one's own, private; akin to Latin suus one's own — more at suicide

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Time Traveler for idiot

The first known use of idiot was in the 14th century

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More Definitions for idiot



English Language Learners Definition of idiot

: a very stupid or foolish person


id·​i·​ot | \ ˈi-dē-ət \

Kids Definition of idiot

: a silly or foolish person


id·​i·​ot | \ ˈid-ē-ət \

Medical Definition of idiot

dated, now offensive
: a person affected with extreme mental retardation

Other Words from idiot

idiot adjective, dated, now offensive

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id·​i·​ot | \ ˈi-dē-ət \

Legal Definition of idiot

: a person with especially a profound intellectual disability

Note: While the terms idiot, imbecile, and moron survive in many state codes and statutes, they are generally no longer used in both medical and legal contexts. The modern terminology distinguishes between mild, moderate, severe, and profound levels of disability. Historically persons with intellectual disabilities have been deprived of certain rights (as in not being allowed to vote). Generally today, an adult with an intellectual disability who is his or her own guardian is not deprived of these rights.

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More from Merriam-Webster on idiot

Thesaurus: All synonyms and antonyms for idiot

Spanish Central: Translation of idiot

Nglish: Translation of idiot for Spanish Speakers

Britannica English: Translation of idiot for Arabic Speakers

Comments on idiot

What made you want to look up idiot? Please tell us where you read or heard it (including the quote, if possible).


to settle judicially or to act as judge

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