undo

verb

un·​do ˌən-ˈdü How to pronounce undo (audio)
ˈən-
undid ˌən-ˈdid How to pronounce undo (audio)
ˈən-
 ; undone ˌən-ˈdən How to pronounce undo (audio)
ˈən-
 ; undoing ˌən-ˈdü-iŋ How to pronounce undo (audio)
ˈən-
Synonyms of undonext

transitive verb

1
: to open or loose by releasing a fastening
2
: to make of no effect or as if not done : make null : reverse
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
c
: seduce sense 3

intransitive verb

: to come open or apart
undoer
ˌən-ˈdü-ər How to pronounce undo (audio)
ˈən-
noun

Synonyms

See All Synonyms & Antonyms in Thesaurus

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.
Resurrecting state control would put an end to an era of local control realized after a statewide campaign and vote in 2012 to undo the state's police board. — arkansasonline.com, 12 Mar. 2025 Unlike some of Trump’s more aggressive executive moves, such as his effort to undo birthright citizenship, his push to remove specific agency heads may better withstand legal challenges from the Left. — Kaelan Deese, Washington Examiner - Political News and Conservative Analysis About Congress, the President, and the Federal Government, 12 Mar. 2025 Given that the public sector is highly unionized and disproportionately provides employment opportunities for women and Black workers, privatization risks undoing these gains. — Nathan Meyers, The Conversation, 11 Mar. 2025 The move would undo one of former President Joe Biden’s highest-profile targets for improving conditions in places harmed by industrial pollution. — Alan Ohnsman, Forbes, 10 Mar. 2025 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

Rhymes for undo

See All Rhymes for undo

Browse Nearby Words

undo
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Cite this Entry

“Undo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undo. Accessed 24 Mar. 2025.

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Kids Definition

undo

verb
un·​do ˌən-ˈdü How to pronounce undo (audio)
ˈən-
undid -ˈdid How to pronounce undo (audio) ; undone -ˈdən How to pronounce undo (audio) ; undoing -ˈdü-iŋ How to pronounce undo (audio)
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

More from Merriam-Webster on undo

Nglish: Translation of undo for Spanish Speakers

Last Updated: - Updated example sentences
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