The sky is usually bright and sunny, but sometimes it can start to darken. This happens when the sun is going to set, or when it's night time.
The sky started to darken as the sun set.
The sky started to darken after the sun had already set.
noun
changing to a darker color
Synonyms:
adjective
becoming dark or darker as from waning light or clouding over
1
Thunder crackles as the sky darkens.
2
Darken is one of the more popular members of.
3
A darkened moon is still faintly visible.
4
The screens disappear, and the lights immediately darken.
5
The warmer the solution, the faster it will darken the metal.
6
There is redness, scaling, darkening of the skin and itching.
7
Again, the skin and eyes of the chestnut will darken quickly.
8
I have used the software to darken the picture.
9
The primary flight feathers darken during the summer.
10
In the darkened theater, the women misinterpret what the man is doing.