folly

folly — noun

1. behaviour or a specific action that shows a serious failure of good judgment, of

1.nounB2
Definition

behaviour or a specific action that shows a serious failure of good judgment, often leading to harm or regret

Example

Eitan thought it was folly to invest all his savings in a single new company.

it + be + folly + to-infinitive — stating an action is unwise

The construction manager's decision to ignore the safety warnings proved a costly folly.

noun phrase: costly folly — a financially damaging mistake

Common collocations
  • sheer folly
  • costly folly
  • act of folly
  • realize the folly of
  • sheer folly
Synonyms
  • foolishness

    less formal; can describe both minor and major errors

  • stupidity

    harsher and more direct than folly; less literary

  • recklessness

    emphasizes lack of caution rather than lack of judgment

  • madness

    much stronger; implies complete irrationality

Antonyms
  • wisdom

    the quality of having good judgment and foresight

Grammar Patterns

folly + of + gerund

it + be + folly + to-infinitive

possessive + folly

Usage Note

More formal and literary than 'stupidity' or 'foolishness.' Often appears in written criticism or serious commentary to describe a decision with major negative consequences. The uncountable form (sheer folly, act of folly) is more common than the countable one (a folly, costly follies).

Common Mistakes

It was a folly to buy cheap shoes.
It was foolish to buy cheap shoes.
'folly' is too strong for minor, everyday mistakes; use 'foolish' for trivial matters.
His folly made everyone laugh at the party.
His foolishness made everyone laugh at the party.
'folly' carries serious consequences, not light social embarrassment.

2. a small building designed to look like a castle, temple, or old ruin, placed on

2.nounC1
Definition

a small building designed to look like a castle, temple, or old ruin, placed on the grounds of a large estate for decoration rather than everyday use

Example

The 18th-century estate has a Gothic folly hidden among the oak trees.

Gothic folly — describing the architectural style

Visitors can explore the crumbling stone folly that overlooks the lake.

Common collocations
  • Gothic folly
  • stone folly
  • temple-shaped folly
  • ornamental folly
Synonyms
  • pavilion

    can also be a decorative garden building, but often has practical use such as shelter

  • gazebo

    open-sided structure offering shade; not a castle or temple replica

Grammar Patterns

adjective + folly

folly + verb

Usage Note

Primarily found in descriptions of British and European country estates from the 18th and 19th centuries. The term often suggests a whimsical or romantic structure that imitates older architectural styles. Not used for functional garden buildings like sheds or greenhouses.

Word family

Synonym discussion

Sense: noun/1

These words all describe a lack of good judgment, but differ in formality and severity. 'Folly' is the most formal and literary — it typically refers to a serious misjudgment with major consequences (e.g., building on a floodplain). 'Foolishness' is milder and everyday; a foolish act might be buying an overpriced item, whereas a folly is a grave error. 'Stupidity' is more direct and harsh, carrying stronger negative judgment. 'Recklessness' focuses on acting without caution rather than without judgment. 'Madness' is the strongest, implying complete irrationality. Example: 'It was sheer folly to ignore the engineer's report' (formal, serious). 'His recklessness on the road caused the accident' (lack of caution). 'The proposal was dismissed as madness' (extreme irrationality).

foolishness ↗stupidity ↗recklessnessmadness ↗

Common collocations

Nouns

Adverbs

Prepositions

Etymology

LatinFrenchEnglish

From Old French 'folie' meaning 'madness, foolishness,' derived from 'fol' (foolish, mad) — the same root that gives modern English 'fool.' The sense of a decorative garden building emerged in the 18th century, possibly from the idea that building such an extravagant and impractical structure was itself an act of foolishness.