1 B2 neutral
Of the sky or a room: to become noticeably darker, often suddenly.
"The sky darkened up in the east, and we knew the rain was coming fast."
inseparable
darken up
B2 neutral inseparable transitive/intransitive
To become noticeably darker, especially of the sky, a colour, or a complexion — often suggesting a rapid or visible change.
In plain English
To quickly get darker in colour or shade.
What does "darken up" mean?
3 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B2 neutral
Of a colour or surface: to become richer or deeper in shade.
"Wet the wood first — it'll darken up nicely and show you the final stained colour."
inseparable
3 B2 informal
Of a person's skin: to become more tanned or darker in tone.
"She darkened up beautifully after two weeks on the Mediterranean coast."
inseparable
Literal vs figurative
Words literally mean
To become dark in an upward or spreading manner.
Actually means
To quickly get darker in colour or shade.
Usage tip
Used in weather, art, beauty, and figurative contexts. In beauty and tanning contexts, 'darken up' can refer to skin becoming more tanned. In atmospheric contexts, it suggests a threatening or dramatic change.
Words that pair with "darken up"
Natural word combinations native speakers use most often.
sky skin tan colour room complexion
How to conjugate "darken up"
The five tense forms you'll use most often.
Base
darken up
I/you/we/they
3rd person
darkens up
he/she/it
Past simple
darkened up
yesterday
Past participle
darkened up
have + pp
-ing form
darkening up
continuous
Hear "darken up" in the wild
Listen to native speakers using "darken up" in real YouTube videos — click a clip to watch it on Looplines.
Keep exploring
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