Undo or undue?
undo is a verb meaning “To reverse the effects of an action”; undue is an adjective meaning “Excessive; going beyond that what is natural or sufficient”. Use undo as a verb and undue as an adjective. In written English (wordfreq, 2021 data) undo is about 1.9 times as common as undue.
What is the difference between undo and undue?
| undo | undue | |
|---|---|---|
| Part of speech | verb, noun | adjective |
| Meaning | To reverse the effects of an action To unfasten An operation that reverses a previous action | Excessive; going beyond that what is natural or sufficient Which ought not to be done; illegal; unjustified |
| Example | Fortunately, we can undo most of the damage to the system by the war | To individuals who despise killings in any form, death penalty is undue punishment |
| Forms | undoes, undoing, undid, undone | none |
| Pronunciation | /ʌnˈduː/ | /ʌnˈdjuː/ /ʌnˈduː/ |
| In writing | 3.7 times per million words | 1.9 times per million words |
Sources: undo and undue in the English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0); written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
Every current meaning of undo and undue
undo
- 1
To reverse the effects of an action
Fortunately, we can undo most of the damage to the system by the war
- 2
An operation that reverses a previous action
How many undos does this program support?
- 3
To unfasten
Could you undo my buckle for me?
- 4
colloquialTo unfasten the clothing of (a person)
PROSTITUTE: Undo me. There's a dear
- 5
To impoverish or ruin, as in reputation; to cause the downfall of
undue
- 1
Excessive; going beyond that what is natural or sufficient
To individuals who despise killings in any form, death penalty is undue punishment
- 2
Which ought not to be done; illegal; unjustified
- 3
Not owing or payable
Source: the English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0); obsolete, archaic, dialect and rare senses left out.
Which is more common, undo or undue?
undo appears 3.7 times per million words; undue 1.9 times per million words.
undo 3.7 times per million wordsundue 1.9 times per million words
Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
How many people search undo vs undue?
“undo vs undue” is searched about 50 times a month on Google and 10 on Bing in the United States. Google counts close variants of a query together (“undue vs undo”, “undo or undue”).
Sources: Google Ads keyword data through DataForSEO and Microsoft Advertising keyword data through DataForSEO, the average month from September 2025 to August 2026.