Where does “folly” come from?

Folly comes from Old French folie, derived from Old French fol, which developed from Latin follis, ultimately from Proto-Indo-European bʰel-.

folly (English): Foolishness; Thoughtless action resulting in...

Definitions

  1. Foolishness; Thoughtless action resulting in...

Ancestry of “folly”, step by step

folly traces back through two separate lines of ancestry.

via Middle English folie

StepLanguageWordMeaning
1Middle EnglishfolieAlternative form of folye
2Old Frenchfoliemadness; insanity
3Old French-ieindicates a feminine noun, often an abstract one
4Latin-iaUsed to form a feminine abstract noun, usually...
5Latin-iusforming adjectives from nouns; nominative neuter...
6Proto-Italic-jōsForms comparative adjectives
7Proto-Indo-European-yósCreates adjectives from noun or verb stems

via Middle English fol

StepLanguageWordMeaning
1Middle EnglishfolAlternative form of fole

Words derived from “folly

Every word from Proto-Indo-European -yós