English to English

noun (n)

• the trait of acting stupidly or rashly(noun.attribute)

  Synonym:
  foolishness, unwiseness
  Antonym:
  wisdom, wiseness
  

  source: wordnet30
• a stupid mistake(noun.act)

  Synonym:
  betise, foolishness, imbecility, stupidity
  

  source: wordnet30
• the quality of being rash and foolish(noun.cognition)

  Example:
  Trying to drive through a blizzard is the height of folly.
  

  Synonym:
  craziness, foolishness, madness
  

  source: wordnet30
• foolish or senseless behavior(noun.act)

  Synonym:
  craziness, foolery, indulgence, lunacy, tomfoolery
  

  source: wordnet30
• The state of being foolish; want of good sense; levity, weakness, or derangement of mind.(noun)

  source: webster1913