1 C1 informal
To gradually reduce the strength, power, or resistance of something or someone.
"Months of negotiations weakened up the opposing side's resolve."
inseparable
weaken up
C1 informal inseparable transitive/intransitive
To become or cause to become gradually weaker; a colloquial intensified form of 'weaken'.
In plain English
To slowly become less strong or to make something less strong.
What does "weaken up" mean?
One main meaning — here's how to use it.
Usage tip
Non-standard and rarely used. The particle 'up' adds little semantic value here. Most native speakers would simply say 'weaken' or use 'soften up'. Learners are advised to prefer those alternatives.
Words that pair with "weaken up"
Natural word combinations native speakers use most often.
resistance structure muscle position
How to conjugate "weaken up"
The five tense forms you'll use most often.
Base
weaken up
I/you/we/they
3rd person
weakens up
he/she/it
Past simple
weakened up
yesterday
Past participle
weakened up
have + pp
-ing form
weakening up
continuous
Hear "weaken up" in the wild
Listen to native speakers using "weaken up" in real YouTube videos — click a clip to watch it on Looplines.
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