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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.

Some businesses - especially in the hospitality sector - have warned this could put companies off hiring young people, undoing the government's efforts to increase youth employment.

From BBC

Kohl’s is trying to undo missteps that included scaling back petite sizes, fine jewelry and private brands in its stores.

From The Wall Street Journal

From that point, England's shot selection was their big undoing.

From BBC

Inheritances can’t undo the past, but I also understand that this feels like an important battle for you in what you see as a long-term pattern.

From MarketWatch

The Yautja are a ruthless culture whose warriors take pride in hunting alone, and Dek’s stubborn adherence to those rules, even as an outcast, is nearly his undoing.

From Salon