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 What’s more, AI is poised to disrupt how companies are structured in the future, undoing the typical organizational hierarchy. Paige McGlauflin, Fortune, 29 Nov. 2023 But the vines died within a few seasons, undone by unfamiliar pests like phylloxera, a tiny insect, or by the intemperately cold winters and hot summers. Alex Mayyasi, Smithsonian Magazine, 28 Nov. 2023 Alliances form, are undone by events, or the crafty maneuvering of crafty maneuverers. Robert Lloyd, Los Angeles Times, 22 Nov. 2023 But, much of that work is undone by the appearance of Diana’s ghost, she who made headlines last month after news leaked that the princess would be shown speaking to Charles and the queen after her passing. Radhika Seth, Vogue, 17 Nov. 2023 The Apple Silicon-era refresh of these systems undoes all of the worst things about the 2016-to-2020 era of Mac design. Andrew Cunningham, Ars Technica, 6 Nov. 2023 Georgia: State case on 2020 election The details: Trump faces 13 state charges for allegedly trying to undo the election results in that state. Perry Stein, Washington Post, 12 Nov. 2023 The whale’s description is a strong reminder that paleontology is a science carried out by people carrying their own biases and has struggled with a legacy of colonialism that is only just beginning to be undone. Riley Black, Smithsonian Magazine, 7 Nov. 2023 Peltz campaigned for PepsiCo to undo its merger between Pepsi and Frito-Lay. Sheryl Estrada, Fortune, 7 Nov. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'undo.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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 11 Dec. 2023.

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

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