Definition of: silly

(sil′ē) adjective ·li·er, ·li·est
1. Destitute of ordinary good sense; simple; foolish; imbecile; fatuous; sometimes, senile.
2. Characterized by or resulting from foolishness or imbecility; stupid: silly talk.
3. Rare Simple; plain; rustic.
4. Colloq. Stunned; dazed, as by a blow.
5. Obs. or Brit. Dial. Frail; feeble; weak; helpless.
6. Scot. Mentally or physically incapable; idiotic; imbecilic.
7. Obs. Scanty; meager. See synonyms under CHILDISH, RIDICULOUS.
—noun plural ·lies Colloq. A silly person. [OE gesælig happy]
—sil′li·ly adverb
—sil′li·ness noun