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Synonyms

foolishness

American  
[foo-lish-nis] / ˈfu lɪʃ nɪs /

noun

  1. lack of wisdom or good judgment; foolish quality.

    Oh, the foolishness of thinking that wealth brings happiness!

  2. foolish talk, ideas, or behavior.

    How could someone with such a clever mind as yourself talk such foolishness?

  3. a foolish act, error, habit, etc..

    Shakespeare, who looks at all men as if from Mount Olympus, notes their foibles and foolishnesses, and yet smiles on them all.


Other Word Forms


Etymology

Origin of foolishness

foolish + -ness


Explanation

Foolishness is nonsense or stupidity; it's acting in a way that is silly or irrational. Throwing a temper tantrum because the lunch line is moving slowly is pure foolishness — your outburst won't make the line move any faster. When your actions show a lack of good sense or solid judgement, you're betraying your foolishness. Impulsively jumping off the garage roof into a pile of leaves is evidence of your foolishness. We can trace this word's origin back to fool and the Old French fol, "idiot," and also "blacksmith's bellows," from a root meaning "blow or swell."

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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.

See Examples For:

Optimists who think the foolishness will blow over are mistaken.

From The Wall Street Journal ● Oct. 16, 2026

Like Mr. Platner, Mr. Duke claimed to have left all that youthful foolishness behind him.

From The Wall Street Journal ● Jun. 28, 2026

As Dickens prophetically reminds us, ours is hardly the first age of wisdom and of foolishness, the first epoch of belief and of incredulity.

From Los Angeles Times ● Sep. 30, 2025

Diomande's act of foolishness just put the tin hat on it.

From BBC ● Sep. 25, 2025

‘But may I beg you to remove that rabbit you sent among us, for he troubles us with his foolishness?’

From "Watership Down: A Novel" by Richard Adams

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