1 [intransitive and transitive]
to become dark, or to make something dark:
The sky darkened and a few drops of rain fell.
a darkened theater
The evening shadows darkened the room.
2 [intransitive and transitive]
to become less hopeful or positive, or to make something like this:
As he got drunker, his mood darkened.
if someone's face darkens, they start to look angry:
The captain's face darkened as he read.
said when you do not want to see someone again - now used humorously