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Synonyms

undo

American  
[uhn-doo] / ʌnˈdu /

verb (used with object)

undid, undone, undoing
  1. to reverse the doing of; cause to be as if never done.

    Murder once done can never be undone.

  2. to do away with; erase; efface.

    to undo the havoc done by the storm.

  3. to bring to ruin or disaster; destroy.

    In the end his lies undid him.

  4. to unfasten by releasing.

    to undo a gate; to undo a button.

  5. to untie or loose (a knot, rope, etc.).

  6. to open (a package, wrapping, etc.).

  7. Archaic. to explain; interpret.


undo British  
/ ʌnˈduː /

verb

  1. (also intr) to untie, unwrap, or open or become untied, unwrapped, etc

  2. to reverse the effects of

  3. to cause the downfall of

  4. obsolete to explain or solve

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • undoable adjective
  • undoer noun

Etymology

Origin of undo

First recorded before 900; Middle English; Old English undōn; cognate with Dutch ontdoen; un- 2, do 1

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

I wish I could go back in time and undo things, but that is impossible.

From Literature

However, undoing decades of Soviet urban planning will not be quick or easy.

From BBC

"Belated fixes cannot undo this harm. We must hold Big Tech accountable for giving abusers the power to victimize women and girls at the click of a button," Ahmed said.

From Barron's

It was only supposed to be for a night, but the next day, no one could find the Harlequin to change it back, and no one else had any idea how to undo the spell.

From Literature

Nearly 137 years later, Democratic Rep. Jonah Wheeler hopes to undo that act as prime sponsor of the proposed amendment.

From The Wall Street Journal