self-defeating

American  

[self-di-fee-ting, self-] / ˈsɛlf dɪˈfi tɪŋ, ˌsɛlf- /

adjective

1. serving to frustrate, thwart, etc., one's own intention or interests.

   His behavior was certainly self-defeating.

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self-defeating British  

adjective

1. (of a plan, action, etc) unable to achieve the intended result

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Explanation

Anything that's self-defeating acts against its own plan or purpose — it's unsuccessful or useless. If you really want to make friends with someone, it would be self-defeating to say something mean to them. If your actions keep the thing you really hope for from working out, they're self-defeating. It's also self-defeating to be drawn to people who will inevitably treat you badly, or to eat foods you know are going to make your stomach hurt later. Behavior that seems destined to harm you — writing your friend's English paper but not your own, for example — is also self-defeating. Defeating stems from the Vuglar Latin diffacere, "destroy or undo."

Example Sentences

But homing in on the annoying and self-defeating aspects of it misses the real story of how the movement changed American society, and the world, for the better—and how Lindy West did too.

From Slate • Mar. 31, 2026

A quick end to a conflict can be tempting but self-defeating.

From The Wall Street Journal • Mar. 2, 2026

It’s an understandable reaction, but it might be self-defeating.

From Barron's • Dec. 12, 2025

The amount of handling errors from exceptionally talented players was maddening - not quite self-defeating, but a little too close for comfort.

From BBC • Jul. 8, 2025

With that self-defeating thought looping in my head, I never caught the bar once that entire week.

From "Courage to Soar" by Simone Biles