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undo

play
verb un·do \ˌən-ˈdü, ˈən-\

Simple Definition of undo

  • : to open or release (something) : to unfasten or loosen (something)

  • : to change or stop the effect of (something)

  • : to cause the failure of (someone or something)

Source: Merriam-Webster's Learner's Dictionary

Full Definition of undo

undid

play \-ˈdid\

undone

play \-ˈdən\

undoing

play \-ˈdü-iŋ\
  1. transitive verb
  2. 1 :  to open or loose by releasing a fastening

  3. 2 :  to make of no effect or as if not done :  make null :  reverse

  4. 3 a :  to ruin the worldly means, reputation, or hopes of <a politician undone by scandal> b :  to disturb the composure of :  upset <she's come undone> c :  seduce 3

  5. intransitive verb
  6. :  to come open or apart

undoer

play \-ˈdü-ər\ noun

Examples of undo in a sentence

  1. You can't undo the past.

  2. The damage cannot be undone.

  3. He was undone by greed.



Before 12th Century

First Known Use of undo

before 12th century


UNDO Defined for Kids

undo

play
verb un·do \ˌən-ˈdü\

Definition of undo for Students

undid

\-ˈdid\

undone

\-ˈdən\

undoing

\-ˈdü-iŋ\

undoes

\-ˈdəz\
  1. 1 :  untie 2, unfasten <Can you undo this knot?>

  2. 2 :  to cancel the effect of :  reverse <The damage cannot be undone.>

  3. 3 :  to cause the ruin or failure of <He was undone by greed.>





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