Etymology Inherited from Middle English folie, from Old French folie (“madness”), from the adjective fol (“mad, insane”).
1
Foolishness that results from a lack of foresight or lack of practicality.
It would be folly to walk all that way, knowing the shops are probably shut by now.
With the voices singing in our ears, saying That this was all folly.1927 August, T[homas] S[tearns] Eliot, “[Ariel Poems.] Journey of the Magi.”, in Collected Poems 1909–1935, London: Faber & Faber […], published September 1954, →OCLC, page 107:
2
Thoughtless action resulting in tragic consequence.
The purchase of Alaska from Russia was termed Seward's folly.
Thames Water has become the latest object lesson in the predictable and predicted folly of privatised monopolies, aided by a regulator that’s an even bigger wet wipe than the fatbergs bunging up the sewers.2023 June 30, Marina Hyde, “The tide is coming in fast on Rishi Sunak – and it’s full of sewage”, in The Guardian:
3
Architecture A fanciful building built for purely ornamental reasons.
A luncheonette in the shape of a coffee cup is particularly conspicuous, as is intended of an architectural duck or folly.
“The Villa Straylight,” said a jeweled thing on the pedestal, in a voice like music, “is a body grown in upon itself, a Gothic folly. […]”1984, William Gibson, chapter 14, in Neuromancer (Sprawl; book 1), New York, N.Y.: Ace Books, →ISBN, page 172:
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It has been a long time since new follies were springing up across the great estates of Britain. But the owners of Doddington Hall, in Lincolnshire, have brought the folly into the 21st century, by building a 30ft pyramid in the grounds of the Elizabethan manor.2014 September 7, “Doddington's garden pyramid is a folly good show”, in The Daily Telegraph, London:
A great deal of eccentricity was expressed through the trend for ruin follies. But it wasn’t only the madness of paranoid earls and fashionable landowners that was encoded in them.2018 April 18, Paul Cooper, “Europe Was Once Obsessed With Fake Dilapidated Buildings”, in The Atlantic:
"You got any money?" he said to me. ¶ "Hell no, maybe enough for a pint of whisky till I get to Denver. What about you?" ¶ "I know where I can get some." ¶ "Where?" "Anywhere. You can always folly a man down an alley, can't you?"1957 September 5, Jack Kerouac, On the Road, London: Penguin Books, published 1976, →ISBN, page 23:
"Anybody got the makin's?" he said. "That's one hell of a thick bunch of canvas, but I follied the seam."2002, Richard Kilroy O'Malley, Hobo: A Depression Odyssey, →ISBN, page 104:
1 more example
Howandever, at the selfsame time, there was a gang of fellas from the valley of kings follying the very same pointy star. And didn't that pointy star point them king-fellas in the direction of Mary's cowstable.2012, Honor Molloy, Smarty Girl: Dublin Savage, Boston, M.A.: Gemma, →ISBN, page 43:
folly
noun
Etymology Uncertain. The most common theory is that term primarily denotes a clump of trees and relates to French feuille, feuillée and English foliage; it has also been suggested that it refers to some perceived connection or resemblance of the named place to an architectural folly, but many places so named have no architectural follies and cannot be named directly for them.
1
A clump of trees, particularly one on the crest of a hill (or sometimes on a stretch of open ground).
Largely obsolete outside place names
'Every hill seems to have a Folly' [...] 'I mean a clump of trees on the top.'1880, Richard Jeffries, Greene Ferne Farm, page vi:
Folly Beach, the next island to the south (batik 3.7), bears the name given it by mariners, who looked for the island's tree-crested dune ridge, a volley or folly of trees, as a navigation guide [...] Probably a lot of East Coast islands bore the temporary name of Folly Beach.2003, Orrin H. Pilkey, Mary Edna Fraser, A Celebration of the World's Barrier Islands, page 69:
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During the 1920s and 1930s, Folly Farms (above) [referencing a photograph of a farmhouse surrounded by large trees] was owned by Mrs. Samuel Pennington Rotan of Pennsylvania, who was involved in the effort to improve medical care for the indigent people around Ways Station. … Folly Farms was originally known as Myrtle Grove …2006, Buddy Sullivan, Richmond Hill, page 52