undo

un-DOO /ʌnˈduː/
verbA2
General

To cancel or reverse the effects of a previous action; to unfasten something.

Can refer to physical objects (buttons) or abstract consequences (damage).

The story behind the word. From Old English 'undon', meaning to open or unfasten. It is one of the oldest 'un-' words in the English language.

Word relationships

  • reverse: Reverse is more formal and often used for processes; undo is more common for specific actions.
  • do: To perform an action.

Commonly confused with

  • unfasten: Unfasten is strictly physical (belts, buttons); undo can be physical or metaphorical.

Word family

  • undone (adjective): Not finished or not fastened.

Collocations

  • undo the damage
  • undo a button
  • undo a mistake

Idioms & expressions

  • undoing (noun)
  • be someone's undoing

Example sentences

  • "What's done cannot be undone." Literature
  • "It took her several minutes to undo the complicated knot in the shoelace." Everyday Life

Memory hook

Control + Z: The universal 'Undo' command on a computer. Reverse it.

When not to use

In formal legal contexts, 'rescind' or 'nullify' might be more appropriate than 'undo'.

Fun facts

  • The phrase 'be someone's undoing' means the cause of someone's failure or ruin.

Related words

unravel, unhinge

Explore more words

revoke, turn back, detach, retract, offset, reduce

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