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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.

Granted, the simplicity of Arnold’s portfolio could be its undoing.

From MarketWatch

Mayo believed it was also likely these managers understood the risk that their investments could be the Labs’ undoing, as competitors used Bell Labs innovations and improved upon them.

From The Wall Street Journal

"No sentence can undo the trauma of what she endured. But we hope today marks the beginning of her journey toward the bright, safe, and happy future she deserves," the judge told the court.

From BBC

“The sector was starting to show signs of improvement. The energy crisis risks undoing all that.”

From The Wall Street Journal

The most common one is that its recent spectacular performance has been its undoing.

From Barron's