undoing

American  

[uhn-doo-ing] / ʌnˈdu ɪŋ /

noun

1. the reversing of what has been done; annulling.

   Synonyms:

   negation, reversal

2. a bringing to destruction, ruin, or disaster.

3. a cause of destruction or ruin.

4. the act of unfastening or loosing.

5. Psychiatry. an unconscious defense mechanism through which an attempt is made to reverse a psychologically unacceptable act by doing its opposite, usually repetitiously, in order to relieve anxiety.

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undoing British  

/ ʌnˈduːɪŋ /

noun

1. ruin; downfall

2. the cause of downfall

   drink was his undoing

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Other Word Forms

• self-undoing adjective

Etymology

Origin of undoing

Middle English word dating back to 1300–50; undo, -ing ¹

Example Sentences

The most common one is that its recent spectacular performance has been its undoing.

From Barron's • Mar. 24, 2026

The specific reasons for Zhang’s undoing remain shrouded in mystery.

From The Wall Street Journal • Feb. 20, 2026

However, undoing decades of Soviet urban planning will not be quick or easy.

From BBC • Jan. 24, 2026

It ultimately proved to be the group’s undoing, Kochuba said.

From MarketWatch • Dec. 31, 2025

“These pills won’t change the way you look. They’ll only affect your brain, undoing what Dr. Cable did to the way your mind works. Then you can decide for yourself how you want to look.”

From "Uglies" by Scott Westerfeld

Related Words

• downfall
• miscalculation