defense mechanism

noun

1
: an often unconscious mental process (such as repression) that makes possible compromise solutions to personal problems
2
: a defensive reaction by an organism

Examples of defense mechanism in a Sentence

She is projecting her anger on you as a defense mechanism. the cell's normal defense mechanisms against infection
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
This signals plant cells to activate a variety of defense mechanisms. Mack Degeurin, Popular Science, 19 Mar. 2025 Infidelity, in this case, becomes an unconscious defense mechanism—a way to reaffirm their internal belief that relationships always end in pain. Mark Travers, Forbes, 23 Feb. 2025 The Saudi negotiations with Iran that China fostered in March 2023, for example, did not reflect a fundamental reorientation of Saudi foreign policy but a sensible defense mechanism at a moment of apparent U.S. weakness. Elliott Abrams, Foreign Affairs, 7 Feb. 2025 And the body's first reaction to any unnatural cell death is to start a defense mechanism. Kristen Jordan Shamus, USA Today, 19 May 2025 See All Example Sentences for defense mechanism

Word History

First Known Use

1909, in the meaning defined at sense 1

Time Traveler
The first known use of defense mechanism was in 1909

Browse Nearby Words

Cite this Entry

“Defense mechanism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/defense%20mechanism. Accessed 5 Jun. 2025.

Medical Definition

defense mechanism

noun
1
: an often unconscious mental process (as repression, projection, or sublimation) that makes possible compromise solutions to personal problems
2
: a defensive reaction by an organism

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