Source : Webster's Revised Unabridged Dictionary (1913)

Brighten \Bright"en\, v. t. [imp. & p. p. {Brightened}; p. pr. &
   vb. n. {Brightening}.]

   Note: [From {Bright}, a.]
   1. To make bright or brighter; to make to shine; to increase
      the luster of; to give a brighter hue to.

   2. To make illustrious, or more distinguished; to add luster
      or splendor to.

            The present queen would brighten her character, if
            she would exert her authority to instill virtues
            into her people.                      --Swift.

   3. To improve or relieve by dispelling gloom or removing that
      which obscures and darkens; to shed light upon; to make
      cheerful; as, to brighten one's prospects.

            An ecstasy, which mothers only feel, Plays round my
            heart and brightens all my sorrow.    --Philips.

   4. To make acute or witty; to enliven. --Johnson.