undo
B2Neutral to informal; formal in technical computing contexts.
Definition
Meaning
To reverse or cancel the effect of a previous action.
To cause something to return to a former state; to unfasten, untie, or loosen something; in computing, to reverse the last command or action.
Linguistics
Semantic Notes
Often implies correcting a mistake or returning to a previous, often preferable, state. It can refer to both physical actions (like untying) and abstract ones (like reversing a decision).
Dialectal Variation
British vs American Usage
Differences
No significant differences in meaning. Spelling remains 'undo' in both. The physical sense 'to unfasten' may be slightly more common in UK than US everyday speech (e.g., 'undo your laces').
Connotations
Identical in both varieties.
Frequency
Virtually identical. High frequency in both due to computing terminology.
Vocabulary
Collocations
Grammar
Valency Patterns
undo + NP (object)be + undone (past participle/passive)NP + can/cannot be undoneVocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “What's done cannot be undone.”
Usage
Context Usage
Business
To reverse a financial transaction or a strategic decision ('We need to undo the merger agreement.').
Academic
To challenge or reverse the findings or effects of previous research ('The new study undoes decades of accepted theory.').
Everyday
To unfasten clothing or to reverse a simple mistake ('Can you undo this jar?' or 'I wish I could undo sending that text.').
Technical
In software, a command that reverses the last edit or action (Ctrl+Z or Cmd+Z).
Examples
By Part of Speech
verb
British English
- You can't undo the damage once it's done.
- She quickly undid the clasp of her necklace.
American English
- Hit Ctrl+Z to undo that edit.
- The scandal undid all his political gains.
adverb
British English
- N/A
American English
- N/A
adjective
British English
- N/A
American English
- N/A
Examples
By CEFR Level
- I made a mistake. Can I undo it?
- Please undo your shoe laces.
- The update broke the app, and we can't undo it easily.
- He undid the parcel to see what was inside.
- The court ruling may undo years of progressive legislation.
- She felt a profound sense of regret for actions she could not undo.
- The economic reforms served to undo the protectionist policies of the previous administration.
- The fabric of their alliance was slowly being undone by mutual suspicion.
Learning
Memory Aids
Mnemonic
Think of the prefix 'UN-' (meaning reverse) + 'DO'. To UNDO is to UN-DO something you have already DONE.
Conceptual Metaphor
TIME AS A PATH: Undoing is like walking backwards on a path to a previous point. ACTION AS A KNOT: A completed action is a tied knot; to undo it is to untie that knot.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid directly translating as 'разделать' (which is very rare). Use 'отменить' for abstract actions (decisions, commands) and 'расстегнуть/развязать' for physical actions (clothing, knots). The computing term is 'отменить' (действие).
Common Mistakes
- Using 'undo' as a noun (e.g., 'I made an undo'). Correct: 'I performed an undo' (computing jargon) or 'I undid it.' Overusing for irreversible actions ('You can't undo death.').
Practice
Quiz
In which context is the use of 'undo' LEAST appropriate?
FAQ
Frequently Asked Questions
No, it's a common verb for reversing any action or unfastening something. The computing use is just one very frequent modern application.
The past simple is 'undid', and the past participle is 'undone' (e.g., 'I undid it yesterday,' 'It has been undone.').
Yes, but primarily in computing/informal contexts (e.g., 'Give it an undo'). In general English, it's almost always a verb.
'What's done cannot be undone' means that some actions are final and their consequences cannot be erased.