folly

[1]	foolishness , foolishness , unwiseness , nonsense , absurdity , daftness , silliness , preposterousness , absurdness , senselessness , fatuousness , fatuity , rashness , stupidity , asininity , inanity , nonsensicalness , idiocy , imbecility , irrationality , lunacy , insanity , madness , craziness , eccentricity , weak-mindedness , feeble-mindedness , simple-mindedness , muddle-headedness , thickheadedness , stolidity , stolidness , obtuseness , brainlessness , (Colloq) dumbness , dopiness , nuttiness , (US/Canadian) kookiness
[2]	absurdity , stupidity , betise , mistake , blunder , foolishness , imbecility , error , faux pas , gaffe , (Colloq) goof , fluff
[3]	foolishness , craziness , madness
[4]	foolery , tomfoolery , craziness , lunacy , indulgence