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Synonyms

foolish

American  
[foo-lish] / ˈfu lɪʃ /

adjective

  1. resulting from or showing a lack of sense; ill-considered: unwise.

    a foolish action;

    a foolish speech.

    Synonyms:
    thoughtless, imprudent, preposterous, nonsensical, absurd, ridiculous, unintelligent, senseless, brainless, witless, stupid
  2. lacking forethought or caution.

    Synonyms:
    thoughtless, imprudent, incautious, heedless, half-baked, foolhardy, reckless, rash, impetuous
  3. trifling, insignificant, or paltry.

    Synonyms:
    picayune, trivial

foolish British  
/ ˈfuːlɪʃ /

adjective

  1. unwise; silly

  2. resulting from folly or stupidity

  3. ridiculous or absurd; not worthy of consideration

  4. weak-minded; simple

  5. an archaic word for insignificant

"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

foolish Idioms  

Usage

What are other ways to say foolish? A foolish action is one that shows a lack of sense or is ill-considered. How is foolish different from fatuous, silly, inane, stupid, and asinine? Find out on Thesaurus.com. 

Other Word Forms

  • foolishly adverb
  • foolishness noun
  • overfoolish adjective
  • overfoolishly adverb
  • quasi-foolish adjective
  • quasi-foolishly adverb
  • unfoolish adjective
  • unfoolishly adverb

Etymology

Origin of foolish

First recorded in 1250–1300; from Middle English folish, foolish; see fool 1, -ish 1

Explanation

Foolish people are silly or senseless, and when you do something foolish, it's clearly unwise or irrational. Sitting on the hood of a car while your friend is driving is a foolish thing to do. Things that show a lack of judgment are foolish, like cheating on a test or running into the street after a basketball. Foolish decisions at work can cost you your job, and foolish comments can hurt people's feelings. Foolish is a 14th century word that comes from fool, a person who's unwise. The Latin root, follis, means "bellows" or "leather bag." The "silly person" meaning comes from the figurative idea of a "windbag."

Keep Reading on Vocabulary.com

Vocabulary lists containing foolish

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.

Wring says his customers all accept it, and "if we don't pass it on, we'd be very foolish".

From BBC • Apr. 22, 2026

The risk, if I had to pick one, is appearing foolish to others in my orbit, including my children, or embarrassing them when we are out together in public.

From The Wall Street Journal • Apr. 18, 2026

But the characters in here make such foolish decisions that they barely seem real either.

From Los Angeles Times • Apr. 9, 2026

Go through the account activity together, framing it as a routine check rather than accusing him of being foolish or incompetent.

From MarketWatch • Mar. 23, 2026

"Don't be foolish," his mom's voice said, but it sounded very nervous.

From "All About Sam" by Lois Lowry