English Reference
noun

undoing

n.
US /ənˈduɪŋ/ UK /ʌndˈuːɪŋ/ un·do·ing UK spelling undoings

  1. 01 B2 Upper Intermediate

    the reason why someone fails or loses their power or success.

    the cause of someone's ruin, downfall, or defeat.

    Simple

    His pride was his undoing, as he refused to listen to any advice.

    In context

    The CEO's obsession with short-term profits eventually proved to be the company's undoing when the long-term infrastructure began to fail.

  2. 02 C1 Advanced Formal

    the act of opening or loosening something that is tied or closed.

    the act of unfastening, loosening, or untying something.

    Simple

    The undoing of the heavy knots took several minutes of hard work.

    In context

    The careful undoing of the ancient scroll required specialized tools to prevent the fragile parchment from crumbling.

    unfasteningopeninguntying
  3. 03 C1 Advanced Formal

    the act of cancelling or changing a previous decision or action.

    the annulment or reversal of a previous action, decision, or effect.

    Simple

    The undoing of the new law caused a lot of confusion in the city.

    In context

    The sudden undoing of years of diplomatic progress left the two nations on the brink of a trade war.

But beyond the economy, Syria would risk undoing much of the work done in building a new unified armed force.

Al Jazeera· 15 Aug 2026

Etymology 1

From Middle English undoinge, undoynge, ondoynge; equivalent to undo + -ing.

Etymology 2

From Middle English undoynge, undoand, from Old English undōnde (“undoing”), from Proto-Germanic andadōndz, present participle of andadōną (“to undo”). Cognate with Dutch ontdoend (“undoing”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Middle English undoinge
Level B2 · Upper Intermediate
Frequency Occasional
Updated