1. (noun)folly, foolishness, unwiseness the trait of acting stupidly or rashly
2. (noun)stupidity, betise, folly, foolishness, imbecility a stupid mistake
3. (noun)folly, foolishness, craziness, madness the quality of being rash and foolish "trying to drive through a blizzard is the height of folly"; "adjusting to an insane society is total foolishness"