1 B1 informal
To contract and display muscles, especially in a pose.
"The bodybuilder flexed up on stage as the judges scored his physique."
flex up
B2 informal intransitive
To tighten and display one's muscles; or figuratively, to increase strength or capability.
In plain English
To squeeze your muscles tight to show how strong you are, or to become stronger and more powerful.
What does "flex up" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B2 idiomatic neutral
To increase strength, capacity, or resources (figurative).
"The military announced it would flex up its presence in the region in response to the threat."
Literal vs figurative
Words literally mean
To flex (contract muscles) upward into a display position — transparent.
Actually means
To squeeze your muscles tight to show how strong you are, or to become stronger and more powerful.
Usage tip
Used in fitness and gym contexts. Figuratively used in business or sports to mean increasing capacity or strength. More common in American English.
Words that pair with "flex up"
Natural word combinations native speakers use most often.
muscles biceps team capacity forces defenses
How to conjugate "flex up"
The five tense forms you'll use most often.
Base
flex up
I/you/we/they
3rd person
flexes up
he/she/it
Past simple
flexed up
yesterday
Past participle
flexed up
have + pp
-ing form
flexing up
continuous
Hear "flex up" in the wild
Listen to native speakers using "flex up" in real YouTube videos — click a clip to watch it on Looplines.
Keep exploring
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