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-​ \

Definition of undo

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
3a : 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

Other Words from undo

undoer \ ˌən-​ˈdü-​ər How to pronounce undo (audio) , ˈən-​ \ noun

Synonyms & Antonyms for undo



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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 Others theorize that this has to do with Ezra Miller’s Flash shenanigans, which remains its own problem, but DC may be trying to undo aspects of that movie, which was also supposed to include Michael Keaton’s Batman. Paul Tassi, Forbes, 3 Aug. 2022 The community would be stepping in, trying to undo the trouble created by men who either can’t or won’t help--during or after the pregnancy--and who did not protect the woman in the first place. cleveland, 21 July 2022 To reverse the downward spiral of social decadence and patriarchal decay, conservatives must undo the liberal culture of rights, starting with the unenumerated rights of substantive due process. Corey Robin, The New Yorker, 9 July 2022 My guess is that many people are going through similar struggles of trying to undo damage. Justin Raystaff Writer, Los Angeles Times, 21 June 2022 And while Depp may have been handed a sweeping legal victory on June 1, that win can’t undo years of a deteriorating public image amid an acrimonious divorce from Heard. Winston Cho, The Hollywood Reporter, 7 June 2022 Today, no state or political party is seriously trying to undo this precedent. Akhil Reed Amar, WSJ, 13 May 2022 There is nothing in the principles of prosecution in any other factors, which prevent us from investigating anyone, anyone who's criminally responsible for an attempt to do undo a democratic election. Pj Elliott, USA TODAY, 21 July 2022 Wisconsin, one of the most divided states in a divided country, gets several close-ups in Mark Bowden and Matthew Teague's new book about persistent efforts to undo the presidential election that knocked Donald Trump out of office. Jim Higgins, Milwaukee Journal Sentinel, 5 Jan. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'undo.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of undo

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

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

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Last Updated

6 Aug 2022

Cite this Entry

“Undo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undo. Accessed 15 Aug. 2022.

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More Definitions for undo


un·​do | \ ˌən-ˈdü How to pronounce undo (audio) \
undid\ -​ˈdid \; undone\ -​ˈdən \; undoing\ -​ˈdü-​iŋ \; undoes\ -​ˈdəz \

Kids Definition of undo

1 : untie sense 2, unfasten Can you undo this knot?
2 : to cancel the effect of : reverse The damage cannot be undone.
3 : to cause the ruin or failure of He was undone by greed.

More from Merriam-Webster on undo

Nglish: Translation of undo for Spanish Speakers

Britannica English: Translation of undo for Arabic Speakers


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