Meaning & use
folly
A lack of good sense; a foolish act, idea, or undertaking, especially one with serious consequences.
See it in a sentence
Investing his entire savings in one stock proved to be a costly folly.
Historians still call the failed expedition an act of sheer folly.
A note on using this word
Folly can be an uncountable quality (sheer folly) or a countable act (his follies); it also names an ornamental building, a distinct architectural sense.
Words with a similar meaning
Choose a synonym to suit the sentence. Meanings can overlap without being identical.
Words with an opposite meaning
Another way to use it
2. noun
An ornamental structure built mainly for decoration, often with no practical purpose, especially on an estate.
A stone tower stood on the hill, a folly built by the estate's original owner.
Make it your own
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