Source : Webster's Revised Unabridged Dictionary (1913)

Frighten \Fright"en\, v. t. [imp. {Frightened}; p. pr. & vb. n.
   {Frightening}.] [See {Fright}, v. t.]
   To disturb with fear; to throw into a state of alarm or
   fright; to affright; to terrify.

         More frightened than hurt.               --Old Proverb.

Source : WordNet®

frighten
     v 1: cause fear in; "The stranger who hangs around the building
          frightens me" [syn: {fright}, {scare}, {affright}]
     2: drive out by frightening