darkening has definitions from the field of color
1
[ adjective ] becoming dark or darker as from waning light or clouding over

Examples

"the darkening sky"

Used in print

(Alex Gordon, The Cipher....)

If Mahzeer was alone with the prime_minister he could be arranging his execution while Hoag stood out here shivering in the darkening street .

Related terms

dark

2
[ adjective ] characterized by hopelessness; filled with gloom

Synonyms

gloomy grim

Examples

"gloomy at the thought of what he had to face" "gloomy predictions" "a gloomy silence" "took a grim view of the economy" "the darkening mood"

Related terms

hopeless

3
[ noun ] (color) changing to a darker color

Synonyms

blackening

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