1 B2 neutral
To make a surface smoother by rubbing or working over it.
"Use fine sandpaper to smooth up the wood before applying the varnish."
separable
smooth up
C1 informal separable transitive
To make something smoother or more refined, often by working over its surface or presentation.
In plain English
To make something neater, more refined, or better by smoothing it.
What does "smooth up" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 C1 idiomatic informal
To refine or polish something — a plan, speech, or presentation — making it more polished.
"Let's smooth up the proposal a bit before we send it to the client."
separable
Literal vs figurative
Words literally mean
To smooth a surface in an upward direction or to bring it to a smooth finish.
Actually means
To make something neater, more refined, or better by smoothing it.
Usage tip
Not a fully standardized phrasal verb. Used occasionally in craft, DIY, and presentation contexts. Less common than 'smooth out' or 'smooth down'. May be encountered in dialect or regional speech.
Words that pair with "smooth up"
Natural word combinations native speakers use most often.
surface edges presentation speech finish wood
How to conjugate "smooth up"
The five tense forms you'll use most often.
Base
smooth up
I/you/we/they
3rd person
smooths up
he/she/it
Past simple
smoothed up
yesterday
Past participle
smoothed up
have + pp
-ing form
smoothing up
continuous
Hear "smooth up" in the wild
Listen to native speakers using "smooth up" in real YouTube videos — click a clip to watch it on Looplines.
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