Definitions of brighten

• make lighter or brighter; "The paint will brighten the room"
• clear up: become clear; "The sky cleared after the storm"
  wordnetweb.princeton.edu/perl/webwn
• To make bright or brighter; to increase the luster of; to give a brighter hue to; To make illustrious, or more distinguished; to add luster or splendor to; (figuratively) To make more cheerful and pleasant; to improve or relieve by dispelling gloom or removing that which obscures and darkens ...
  en.wiktionary.org/wiki/brighten
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• Make or become more light
• make something more attractively and cheerfully colourful
• make or become happier and more cheerful