1 B2 neutral
To expand or curve outward in a smooth, full, rounded way, especially of fabric or sails catching air.
"The sails swelled out as the wind picked up and the yacht began to move."
inseparable
swell out
B2 neutral inseparable intransitive
To expand or curve outward in a rounded, full way, as when wind fills a sail or fabric billows.
In plain English
To push outward and become rounder or bigger, like a sail filling with wind.
What does "swell out" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B2 neutral
To become inflated or distended outward, of a physical structure or body part.
"The walls of the old warehouse had begun to swell out under the weight of the stored grain."
inseparable
Literal vs figurative
Words literally mean
To swell in an outward direction — expanding away from a centre point.
Actually means
To push outward and become rounder or bigger, like a sail filling with wind.
Usage tip
More commonly used for non-bodily expansion — sails, fabric, walls — than for medical swelling (for which 'swell up' is preferred). Has a slightly literary or descriptive quality. Less common in everyday speech.
Words that pair with "swell out"
Natural word combinations native speakers use most often.
sails fabric chest walls curtains belly
How to conjugate "swell out"
The five tense forms you'll use most often.
Base
swell out
I/you/we/they
3rd person
swells out
he/she/it
Past simple
swelled out
yesterday
Past participle
swelled out
have + pp
-ing form
swelling out
continuous
Hear "swell out" in the wild
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Other ways to say "swell out"
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