9
darken(verb, worsen, lighten, unlit, shaded)
4
depress(verb, worsen, darken)
4
dim(verb, clear, obscure, darken)
4
dull(verb, adjective, worsen, darken)
3
fade(verb, rise, extend, grow, lose)
3
cloud
3
upset(verb, worsen, darken)
2
blighted
2
blacken
2
discolor(verb, clean, fading, hue)
2
overcast
2
sadden
1
become rotten
1
bedim
1
befog
1
black
1
blur
1
dampen(verb, spoil)
1
deepen(verb, worsen, darken)
1
dishearten(verb, worsen, darken)
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APASmart Define. (2015). brighten thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/brighten/thesaurus/antonyms
ChicagoSmart Define. 2015. "brighten thesaurus" https://smartdefine.org/brighten/thesaurus/antonyms (accessed September 24, 2026).
HarvardSmart Define 2015, brighten thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/brighten/thesaurus/antonyms>.
MLASmart Define. "brighten thesaurus" 10 April 2015. Web. 24 September 2026. <https://smartdefine.org/brighten/thesaurus/antonyms>