From The Collaborative International Dictionary of English v.0.48 [gcide]:
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.
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2. To make illustrious, or more distinguished; to add luster
or splendor to.
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The present queen would brighten her character, if
she would exert her authority to instill virtues
into her people. --Swift.
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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.
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An ecstasy, which mothers only feel,
Plays round my heart and brightens all my sorrow.
--Philips.
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4. To make acute or witty; to enliven. --Johnson.
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From The Collaborative International Dictionary of English v.0.48 [gcide]:
Brighten \Bright"en\, v. i. [AS. beorhtan.]
To grow bright, or more bright; to become less dark or
gloomy; to clear up; to become bright or cheerful.
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And night shall brighten into day. --N. Cotton.
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And, all his prospects brightening to the last,
His heaven commences ere world be past. --Goldsmith.
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From WordNet (r) 3.0 (2006) [wn]:
brighten
v 1: make lighter or brighter; "The paint will brighten the
room" [syn: brighten, lighten up, lighten] [ant:
darken]
2: become clear; "The sky cleared after the storm" [syn: {clear
up}, clear, light up, brighten] [ant: cloud,
overcast]