Synonyms of undonext

transitive verb

1
: to open or loosen by releasing a fastening
undid her jacket
2
: to make of no effect or as if not done : make null : reverse
The damage cannot be undone.
3
a
: to ruin the worldly means, reputation, or hopes of
a politician undone by scandal
b
: to disturb the composure of : upset
she's come undone

intransitive verb

: to come open or apart

Examples of undo in a Sentence

You can't undo the past. The damage cannot be undone. He was undone by greed.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The credibility finding is the harder one to undo in a second application. Aj Dhaliwal, Forbes.com, 29 Aug. 2026 The tired girl aesthetic runs on light makeup that stays sheer, smudged and undone rather than heavily blended or set. Ashley Lynch, Miami Herald, 28 Aug. 2026 Even some moderate Republicans who were skeptical of the original bill — who could also have a political reason to support rollbacks — don’t see a clear way to undo the cuts. Daniel Payne, STAT, 27 Aug. 2026 Now a last-minute, end-of-session proposal in the Legislature threatens to undo that progress. Brandon Okita, Oc Register, 27 Aug. 2026 See All Example Sentences for undo

Word History

First Known Use

before the 12th century, in the meaning defined at transitive sense 1

Time Traveler
The first known use of undo was before the 12th century

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Cite this Entry

“Undo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undo. Accessed 1 Sep. 2026.

Kids Definition

1
: to make or become unfastened or loosened : open, untie
undo a knot
2
: to destroy the effect of : nullify, reverse
3
a
: to cause the ruin of
your stubbornness undid you
undone by greed
b
: to disturb the calmness of : upset
she's come undone
undoer noun
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