1.a word used for misbehaving children;
don't be a silly
2.pungent adjectives of disesteem;
gave me a cockamamie reason for not going
3.lacking seriousness; given to frivolity;
a dizzy blonde
4.inspiring scornful pity;
how silly an ardent and unsuccessful wooer can be especially if he is getting on in years- Dashiell Hammett
5.dazed from or as if from repeated blows;
knocked silly by the impact