Definition of folly
1 : lack of good sense or normal prudence and foresight his folly in thinking he could not be caught
3 : a foolish act or idea The prank was a youthful folly.
4 : an excessively costly or unprofitable undertaking Paying so much for that land was folly, since it was all rocks and scrub trees.
5 : an often extravagant picturesque building erected to suit a fanciful taste
Examples of folly in a sentence
the folly of driving fast on steep, winding roads
his folly in thinking that he would not be noticed
The folly of such an action should be apparent to everyone.
the follies of the modern world
the famous Ziegfeld Follies of the 1920s
Origin and Etymology of folly
Middle English folie, from Anglo-French, from fol fool
First Known Use: 13th century
FOLLY Defined for English Language Learners
Definition of folly for English Language Learners
: the lack of good sense or judgment
: a foolish act or idea : foolish behavior
: a very unusual or fancy building that was built in a garden for decoration or amusement in the past
FOLLY Defined for Kids
Definition of folly for Students
1 : lack of good sense His own folly caused his trouble.
2 : a foolish act or idea That plan was sheer folly.
Seen and Heard
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