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-

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

intransitive verb

: to come open or apart
undoer noun

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.
But even a bit of late-season luck wouldn’t undo the hardship of the growing season. Christine Condon, Baltimore Sun, 29 Nov. 2024 Opponents maintain concerns about ultimate choices that can never be undone and the danger of manipulation and exploitation from third parties despite the bill's stringent safeguards. Gus Alexiou, Forbes, 29 Nov. 2024 For me, there is no funk that can’t be undone by a lush bathrobe, a musky candle, and a face mask. Channing Smith, Glamour, 27 Nov. 2024 Even if these developmental divergences are, in part, the result of toxic elements, removing those elements from the body later on will not undo the physiological or neurological shifts that have already taken place. Lauren Leffer, Popular Science, 27 Nov. 2024 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

Dictionary Entries Near undo

Cite this Entry

“Undo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undo. Accessed 6 Dec. 2024.

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

Last Updated: - Updated example sentences
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