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fool

1 American  
[fool] / ful /

noun

  1. a silly or stupid person; a person who lacks judgment or sense.

    Synonyms:
    sap, saphead, booby, nincompoop, ninny, dunderhead, ignoramus, numbskull, blockhead, dunce, dolt, simpleton
    Antonyms:
    genius
  2. a professional jester, formerly kept by a person of royal or noble rank for amusement.

    the court fool.

    Synonyms:
    clown, zany
  3. a person who has been tricked or deceived into appearing or acting silly or stupid.

    to make a fool of someone.

  4. an ardent enthusiast who cannot resist an opportunity to indulge an enthusiasm.

    He's just a dancing fool.

  5. a weak-minded or idiotic person.


verb (used with object)

  1. to trick, deceive, or impose on.

    They tried to fool him.

    Synonyms:
    gudgeon, dupe, cozen, hoax, gull, cheat, hoodwink, delude

verb (used without object)

  1. to act like a fool; joke; play.

  2. to jest; pretend; make believe.

    I was only fooling.

verb phrase

  1. fool away to spend foolishly, as time or money; squander.

    to fool away the entire afternoon.

  2. fool around (with)

    1. to putter aimlessly; waste time.

      She fooled around all through school.

      I fooled around with painting for a bit, but never got anywhere with it.

    2. Also fool with to handle or play with idly or carelessly.

      She was hurt while fooling around with a loaded gun.

      It's unkind to fool with someone's affections.

    3. to flirt or have casual sexual encounters.

      You should know better than to fool around with someone you work with.

      They're just fooling around–I don't think the relationship is going to go anywhere.

    4. to be sexually promiscuous, especially to engage in adultery.

      He's out fooling around while she's at home sick with the flu.

idioms

  1. be nobody's fool, to be wise or shrewd.

fool 2 American  
[fool] / ful /

noun

British Cooking.
  1. a dish made of fruit, scalded or stewed, crushed and mixed with cream or the like.

    gooseberry fool.


fool 1 British  
/ fuːl /

noun

  1. a person who lacks sense or judgement

  2. a person who is made to appear ridiculous

  3. (formerly) a professional jester living in a royal or noble household

  4. obsolete an idiot or imbecile

    the village fool

  5. to play the fool or behave irritatingly

  6. a wise or sensible person

  7. to deliberately act foolishly; indulge in buffoonery

"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

verb

  1. (tr) to deceive (someone), esp in order to make him or her look ridiculous

  2. informal (intr; foll by with, around with, or about with) to act or play (with) irresponsibly or aimlessly

    to fool around with a woman

  3. (intr) to speak or act in a playful, teasing, or jesting manner

  4. to squander; fritter

    he fooled away a fortune

  5. to move or proceed in a leisurely way

"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

adjective

  1. informal short for foolish

"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
fool 2 British  
/ fuːl /

noun

  1. a dessert made from a purée of fruit with cream or custard

    gooseberry fool

"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

fool More Idioms  

    More idioms and phrases containing fool


Other Word Forms

  • unfooled adjective
  • unfooling adjective
  • well-fooled adjective

Etymology

Origin of fool1

First recorded in 1225–75; Middle English fol, fool, from Old French fol, from Latin follis “bellows, bag”; follis

Origin of fool2

First recorded in 1590–1600; probably special use of fool 1; trifle ( def. ) (in the sense “a dessert consisting of custard and cake”

Explanation

In the Middle Ages, a fool was a clown or jester. Today, fools are simply silly people who clown around or lack common sense. The original fools were clowns hired by the king for entertainment. They were actually witty and smart, but today's fools are not. When you call someone a fool, you either mean he's gullible or just a run-of-the-mill idiot. To fool also means to play a trick or hoax on someone, and fooling around is carelessly spending time on something silly. If someone doesn't believe something you said, you might defend yourself by saying, "I'm not fooling!"

Keep Reading on Vocabulary.com

Vocabulary lists containing fool

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The documents describe an elaborate hoax in which the defendants allegedly created fake companies and fraudulent email accounts and driver’s licenses to help fool lenders into loaning them huge sums of money.

From Los Angeles Times • Apr. 16, 2026

Few listened, and Merrill looked like a fool.

From The Wall Street Journal • Mar. 31, 2026

Falsified documents were used to hide the trail to China, and non-working "dummy" replica servers were kept in stock to fool auditors, according to the indictment.

From Barron's • Mar. 20, 2026

And the message-board-born concept of a “lolcow,” a gullible user who can be goaded into making a fool of themselves on a regular basis, definitely predated the music video.

From Salon • Feb. 16, 2026

But without, he wasn’t that much of a fool, to think he could take on the Prince of Demons.

From "Night Owls" by A.R. Vishny