undo

[ uhn-doo ]

/ ʌnˈdu /

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See synonyms for: undo / undid / undoing / undone on Thesaurus.com

verb (used with object), un·did

[uhn-did], /ʌnˈdɪd/, un·done

[uhn-duhn], /ʌnˈdʌn/, un·do·ing.

to reverse the doing of; cause to be as if never done: Murder once done can never be undone.

to do away with; erase; efface: to undo the havoc done by the storm.

to bring to ruin or disaster; destroy: In the end his lies undid him.

to unfasten by releasing: to undo a gate; to undo a button.

to untie or loose (a knot, rope, etc.).

to open (a package, wrapping, etc.).

Archaic. to explain; interpret.

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Origin of undo

First recorded before 900; Middle English; Old English undōn; cognate with Dutch ontdoen; see origin at un-², do¹

OTHER WORDS FROM undo

un·do·a·ble, adjective

WORDS THAT MAY BE CONFUSED WITH undo

undo , undue

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use undo in a sentence

As reporters reveled largely in the jolly questions of who done it and who undone it, internet basements simmered with scolding.
Who's Really to Blame for the Monolith Shitshow|Mark Sundeen|December 4, 2020|Outside Online
We have spent years now trying to undo the damage of products like this, seeking out whole ingredients and foods that our grandparents would have considered suitable for the table.
The McRib is back at McDonald’s, and after a taste, I still don’t get its cult appeal|Tim Carman|December 3, 2020|Washington Post
Tabb says that such changes, along with fierce competition, may eventually even lead brokerages to reimpose commissions, undoing the era that Robinhood ushered in.
Robinhood’s next adventure: Stealing market share from the rich|Jeff|December 3, 2020|Fortune
In November, voters rejected an effort to undo another piece of Wilson’s legacy.
San Diego’s Pete Wilson Statue Is Back|Sara Libby|December 2, 2020|Voice of San Diego

Long gone are the days of tangled up wires that take forever to undo.
Best wireless headphones: Five things to consider|Carsen Joenk|November 25, 2020|Popular-Science
It undoes some of the progress made after 9/11 to push information out of agency silos and share it widely across the government.
WikiLeaks’ Harmful New Dump|P.J. Crowley|August 31, 2011|DAILY BEAST
Then Yvette, who is married to an older intellectual, undoes her skirt and waits for Salim in his bed.
Naipaul's Art of Darkness|Amitava Kumar|December 26, 2008|DAILY BEAST
Every gain on the wrong side undoes the effect of many conquests on the right.
Your Mind and How to Use It|William Walker Atkinson
It undoes in a moment all that we have accomplished in a long while.
Health Through Will Power|James J. Walsh
Then he goes to the tent, undoes a hook, and again stands gazing over the sea; then turns round, and resumes his walk as before.
Fridtjof Nansen|Jacob B. Bull
Again the man on the watch arrests his steps; he undoes another hook in the tent.
Fridtjof Nansen|Jacob B. Bull
But now let us wait and see what this winter does or undoes—while God does His part for good, as we know.
The Letters of Robert Browning and Elizabeth Barrett Barrett, Vol. 1 (of 2) 1845-1846|Robert Browning and Elizabeth Barrett Barrett

British Dictionary definitions for undo

undo

/ (ʌnˈduː) /

verb -does, -doing, -did or -done (mainly tr)

(also intr) to untie, unwrap, or open or become untied, unwrapped, etc

to reverse the effects of

to cause the downfall of

obsolete to explain or solve

Derived forms of undo

undoer, noun

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

undo

Origin of undo

OTHER WORDS FROM undo

WORDS THAT MAY BE CONFUSED WITH undo

Words related to undo

How to use undo in a sentence

British Dictionary definitions for undo

Derived forms of undo