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definitions

idiot

[id-ee-uht]
See more synonyms for idiot on Thesaurus.com
noun
  1. Informal. an utterly foolish or senseless person: If you think you can wear that outfit to a job interview and get hired, you're an idiot!
  2. Psychology. (no longer in technical use; considered offensive) a person of the lowest order in a former and discarded classification of mental retardation, having a mental age of less than three years old and an intelligence quotient under 25.

Origin of idiot

1250–1300; Middle English < Latin idiōta < Greek idiṓtēs private person, layman, person lacking skill or expertise, equivalent to idiō- (lengthened variant of idio- idio-, perhaps by analogy with stratiōtēs professional soldier, derivative of stratiá army) + -tēs agent noun suffix
Related formsid·i·ot·ic, adjective

Synonyms for idiot

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1. fool, half-wit; imbecile; dolt, dunce, numskull.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for idiot

fool, jerk, twit, nitwit, stupid, moron, kook, bonehead, dumbbell, dunce, blockhead, imbecile, ninny, tomfool, pinhead, ignoramus, simpleton, nincompoop, cretin, dimwit

Examples from the Web for idiot

Contemporary Examples of idiot

Historical Examples of idiot

  • Yet in reviewing it you speak of it as the work of the Idiot of the Century.

  • One pool, a backset, was known as the Idiot's Delight, because any one could catch fish there.

    The Forest

    Stewart Edward White

  • Idiot though she might be, surely Mr. Wilcox was more—how should one put it?

    Howards End

    E. M. Forster

  • Idiot was one of the terms, the mildest, which I should have applied to that young man.

    The Rise of Roscoe Paine

    Joseph C. Lincoln

  • Idiot that he is, he must know that this situation can last but a short time.

    Up the Forked River

    Edward Sylvester Ellis

British Dictionary definitions for idiot

idiot

noun
  1. a person with severe mental retardation
  2. a foolish or senseless person

Word Origin for idiot

C13: from Latin idiōta ignorant person, from Greek idiōtēs private person, one who lacks professional knowledge, ignoramus; see idio-
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for idiot
n.

early 14c., "person so mentally deficient as to be incapable of ordinary reasoning;" also in Middle English "simple man, uneducated person, layman" (late 14c.), from Old French idiote "uneducated or ignorant person" (12c.), from Latin idiota "ordinary person, layman; outsider," in Late Latin "uneducated or ignorant person," from Greek idiotes "layman, person lacking professional skill" (opposed to writer, soldier, skilled workman), literally "private person (as opposed to one taking part in public affairs)," used patronizingly for "ignorant person," from idios "one's own" (see idiom).

Reader, suppose you were an idiot. And suppose you were a member of Congress. But I repeat myself. [Mark Twain, c.1882]

Idiot box "television set" is from 1959; idiot light "dashboard warning signal" is attested from 1968. Idiot savant attested by 1870.

Online Etymology Dictionary, © 2010 Douglas Harper
idiot in Medicine

idiot

[ĭd′ē-ət]
n.
  1. A person of profound mental retardation having a mental age below three years and generally being unable to learn connected speech or guard against common dangers. The term belongs to a classification system no longer in use and is now considered offensive.
Related formsid′i•ot′ic (-ŏt′ĭk) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.