early 13c., "mental weakness; foolish behavior or character; unwise conduct" (in Middle English including wickedness, lewdness, madness), from Old French folie "folly, madness, stupidit [..]

silliness.

An art form developed by the hide bound in which the same old mistakes are made, but different results are expected. [D03862]

A structure with no purpose besides decoration

A Folly is a garden structure which can be seen as a folly (by its owner or by visitors) because of its appearance, cost or lack of utility (eg a sham castle, an artificial ruin or a hermit's cel [..]

a garden building built primarily for visual effect: to "fool" the eye.

An extravagant or outlandish construction, meant either only for garden decor or serving some function other than the one for which it appears to be made, such as a faux ruined castle that actually se [..]

the trait of acting stupidly or rashly stupidity: a stupid mistake the quality of being rash and foolish; "trying to drive through a blizzard is the height of folly"; &am [..]

silliness; a foolish action

Foolishness, silliness.

(n) the trait of acting stupidly or rashly(n) a stupid mistake(n) the quality of being rash and foolish(n) foolish or senseless behavior

insania

Father of Folly (Abu Jahl), an aged chief, who led a hundred horse and seven hundred camels against Mahomet and fell at the battle of Bedr. His own people called him Father of Wisdom (Abu’ Lh [..]

A decorative building or structure often built as part of a landscaped park

, in Lincolnshire, have brought the folly into the 21st century, by building a 30ft pyramid in the grounds of the Elizabethan manor.}}