1 B1 neutral
Of the sky: to become filled with clouds, often before rain.
"It was a beautiful morning, but it started to cloud up around lunchtime."
inseparable
cloud up
B1 neutral inseparable intransitive
Of the sky: to become covered with clouds; also of a surface: to become misty or foggy.
In plain English
When clouds fill up the sky, or when a glass or mirror gets all steamy and you can't see through it.
What does "cloud up" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B2 neutral
Of a glass surface or eyes: to become misty, blurred, or obscured.
"The bathroom mirror clouded up from the steam as soon as she started the shower."
inseparable
Literal vs figurative
Words literally mean
To become filled ('up') with clouds ('cloud').
Actually means
When clouds fill up the sky, or when a glass or mirror gets all steamy and you can't see through it.
Usage tip
The weather sense is very similar to 'cloud over.' The sense of a surface becoming opaque is slightly different and often applied to glass, lenses, or eyes. Common in everyday American and British English.
Words that pair with "cloud up"
Natural word combinations native speakers use most often.
sky glass mirror eyes weather lens
How to conjugate "cloud up"
The five tense forms you'll use most often.
Base
cloud up
I/you/we/they
3rd person
clouds up
he/she/it
Past simple
clouded up
yesterday
Past participle
clouded up
have + pp
-ing form
clouding up
continuous
Hear "cloud up" in the wild
Listen to native speakers using "cloud up" in real YouTube videos — click a clip to watch it on Looplines.
Keep exploring
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