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-​ \

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

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Other Words from undo

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

Synonyms & Antonyms for undo

Synonyms

Antonyms

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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.
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Recent Examples on the Web The same could happen in this case, with the court making the temporary injunction a permanent one, but the court could also side with the city and undo the restrictions. Kevin Rector, Los Angeles Times, "Judge grants preliminary injunction limiting LAPD projectile weapons at protests," 10 May 2021 The claim was that the person who could undo the Gordian knot would become master of Asia. Arthur Herman, Forbes, "Quantum Technology: Cutting The Supply Chain Knot," 6 May 2021 Proposals to raise or undo the cap have since been discussed as part of the stimulus packages passed during the Covid-19 pandemic. New York Times, "Why a $10,000 Tax Deduction Could Hold Up Trillions in Stimulus Funds," 1 May 2021 The Senate approved a resolution Wednesday that would undo an environmental rollback by President Donald Trump that relaxed requirements of a 2016 Obama administration rule targeting methane emissions from oil and gas drilling. Matthew Daly, Anchorage Daily News, "Senate votes to reinstate methane rules loosened by Trump," 29 Apr. 2021 The Senate approved a resolution Wednesday that would undo an environmental rollback by President Donald Trump that relaxed requirements of a 2016 Obama administration rule targeting methane emissions from oil and gas drilling. Carl Weiser, The Enquirer, "Ohio's Sen. Rob Portman one of most frequent Republican backers of President Biden's agenda," 29 Apr. 2021 The Senate approved a resolution Wednesday that would undo an environmental rollback by President Donald Trump that relaxed requirements of a 2016 Obama administration rule targeting methane emissions from oil and gas drilling. Matthew Daly, Star Tribune, "Senate votes to reinstate methane rules loosened by Trump," 28 Apr. 2021 The Senate is set to take up a resolution Wednesday that would undo an environmental rollback by President Donald Trump that relaxed requirements of a 2016 Obama administration rule targeting methane emissions from oil and gas drilling. Matthew Daly, ajc, "Democrats move to reinstate methane rules loosened by Trump," 28 Apr. 2021 But last week, even as the case works its way through the court system, the Florida Legislature passed a bill that could hinder residents’ legal options and undo the most significant challenge to sugar cane burning, and the industry, in years. Lulu Ramadan, ProPublica, "“They’re Trying to Make It So We Walk Away”: It’s About to Get Harder to File Lawsuits Saying Sugar Harvesters Poisoned the Air," 28 Apr. 2021

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.

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First Known Use of undo

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

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Time Traveler for undo

Time Traveler

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

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Statistics for undo

Last Updated

14 May 2021

Cite this Entry

“Undo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undo. Accessed 17 May. 2021.

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More Definitions for undo

undo

verb

English Language Learners Definition of undo

: to open or release (something) : to unfasten or loosen (something)
: to change or stop the effect of (something)
formal : to cause the failure of (someone or something)

undo

verb
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

Thesaurus: All synonyms and antonyms for undo

Nglish: Translation of undo for Spanish Speakers

Britannica English: Translation of undo for Arabic Speakers

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