WordWeb Online

1. The trait of acting stupidly or rashly
   - folly, unwiseness
    
2. The quality of being rash and foolish
   "adjusting to an insane society is total foolishness";
   - folly, craziness, madness, nuttiness [informal], insanity
    
3. A stupid mistake
   - stupidity, bêtise, folly, imbecility

Type of: daftness [informal], error, fault, mistake, stupidity, trait

Antonym: wiseness

Encyclopedia: Foolishness