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Definition of "undo" []

  • To reverse or erase; annul: impossible to undo the suffering caused by the war. (verb-transitive)
  • To untie, disassemble, or loosen: undo a shoelace. (verb-transitive)
  • To open (a parcel, for example); unwrap. (verb-transitive)
  • To cause the ruin or downfall of; destroy. (verb-transitive)
  • To throw into confusion; unsettle. (verb-transitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Use "undo" in a sentence
  • "Leaving your parents out of your lives can result in undo stress, as then you will have to deal with their protests or their anquish over you."
  • "Mandela added that economic development would, however, in the longer term undo the socio-economic conditions responsible for a large part of the problem of crime."
  • "Yet he realized that were Henry to be entrusted with the regency he would change in the most radical fashion the course of the ship of state; would introduce measures dear to the late Emperor Frederick, but to which he, the kaiser, was unalterably opposed, and would, in short, undo everything that he himself had done; so that when eventually the crown prince came of age there would be no longer any possibility of his continuing his father's policy, a policy which the emperor has been at great pains to inculcate into his boy."