1 B1 idiomatic informal
To gain a significant amount of weight or body fat, often quickly.
"He packed on ten kilos over the winter and decided it was time to join a gym."
separable
pack on
B1 informal separable transitive
To gain weight or muscle, especially in a noticeable or rapid way.
In plain English
Gain a lot of weight or muscle quickly.
What does "pack on" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B1 idiomatic informal
To deliberately build up muscle mass through training and diet.
"The actor packed on 15 pounds of muscle in just six months to prepare for the superhero role."
separable
Literal vs figurative
Words literally mean
To pack something onto a surface — the idiomatic meaning maps onto adding mass to a body.
Actually means
Gain a lot of weight or muscle quickly.
Usage tip
Almost always used with 'pounds', 'weight', 'muscle', or 'kilos'. Common in fitness and diet contexts. Used in both British and American English.
Words that pair with "pack on"
Natural word combinations native speakers use most often.
pounds weight muscle kilos mass fat
How to conjugate "pack on"
The five tense forms you'll use most often.
Base
pack on
I/you/we/they
3rd person
packs on
he/she/it
Past simple
packed on
yesterday
Past participle
packed on
have + pp
-ing form
packing on
continuous
Hear "pack on" in the wild
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