undo

To reverse the effects of an action.

Adjective

  1. Misspelling of undue.

Noun

  1. An operation that reverses a previous action.
    • How many undos does this program support?

Origin

From Middle English undōn, from Old English ondōn, from Proto-West Germanic *andadōn (“to undo”), equivalent to un- + do. Cognate with West Frisian ûndwaan, ûntdwaan (“to undo; rid”), Dutch ontdoen (“to undo”).

Forms

undos

Verb

  1. To reverse the effects of an action.
    • Fortunately, we can undo most of the damage to the system by the war.
    • What's done can't be undone.
    • Pro.[…]it was a torment / To lay vpon the damn'd, which Sycorax / Could not againe vndoe ; it was mine Art, / When I arriu'd, and heard thee, that made gape / The Pyne, and let thee out. - 1610–1611 (date written),...
  2. To unfasten.
    • Could you undo my buckle for me?
  3. To unfasten the clothing of (a person).
    • PROSTITUTE: Undo me. There's a dear. - 1971, Dr Jekyll and Sister Hyde (film)
  4. To impoverish or ruin, as in reputation; to cause the downfall of.
    • Woe is me, for I am undone! - 1611, The Holy Bible, […] (King James Version), London: […] Robert Barker, […], →OCLC:

Forms

undoes undoing undid undone

Synonyms

cancel reverse unbuckle unbutton untie unzip

Antonyms

redo do up button button up tie up zip zip up

Derived

what's done cannot be undone