1
Weaken credibility
Reduce the degree to which a person, source, or conclusion is trusted.
Example
Repeated contradictions undermined the witness's credibility.
undermine
/ˌʌndəˈmaɪn/ · un-duh-MYNverb
To weaken, erode, or reduce confidence in something.
Use undermine when evidence, behaviour, or hidden damage gradually weakens support, credibility, authority, or structural stability.
What undermine Really Means
The word becomes easier to use when its closely related senses are separated and compared.
2
Weaken an argument
Introduce evidence or reasoning that makes a claim less convincing.
Example
The uncontrolled variable undermines confidence in the study's conclusion.
3
Erode stability
Gradually damage the foundation or effective functioning of a system.
Example
Persistent water leakage undermined the wall's foundation.
Use undermine Naturally
Notice how the surrounding noun or clause reveals the exact shade of meaning.
Repeated contradictions undermined the witness's credibility.
A small sample can undermine the reliability of a broad conclusion.
Secret exceptions undermined public confidence in the policy.
Precision Matters
Undermine overlaps with several common words, but each carries a different emphasis.
undermine
vs.Often works indirectly or gradually against credibility or support.
weaken
Is the broad verb for making something less strong.
undermine
vs.Makes a claim less convincing without necessarily disproving it.
refute
Shows that a claim is false.
undermine
vs.Can damage a position through evidence, behaviour, or conditions.
contradict
Directly states or shows the opposite of a proposition.
undermine
vs.May occur unintentionally through flaws or evidence.
sabotage
Usually implies deliberate action intended to cause failure.
Test undermine in Context
The uncontrolled factor makes the causal conclusion less trustworthy.
1
Because the researchers did not control for participants' prior training, that variable could ___ confidence in the claim that the programme alone caused the improvement.