Folly definition
An act of folly.
Regretted the follies of his youth.
The purchase of Alaska from Russia was termed Seward's folly.
An example of folly is someone intentionally stabbing their foot with a pitch fork.
An example of folly is building a hospital on an earthquake fault line.
A luncheonette in the shape of a coffee cup is particularly conspicuous, as is intended of an architectural duck or folly.