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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; fool 1, -ish 1

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.

"Their foolish screed sows doubt and confusion — which only puts our warriors in danger," he wrote, singling out Kelly as the only one of the six who is still subject to the UCMJ.

From BBC

“Their foolish screed sows doubt and confusion—which only puts our warriors in danger.”

From The Wall Street Journal

Washington would be foolish to mess with it.

From The Wall Street Journal

As Almond explained, when a person is “so depleted,” it becomes more likely they will do something “foolish.”

From Salon

Ms Rope said she thought it would be "a foolish move" and one that would not go down well.

From BBC