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.
Real relationships, however, are the best defense against our own defense mechanisms. Shani Harmon, Forbes.com, 25 June 2025 In this case, the gator used the death roll as a defense mechanism, officials said. Melina Khan, USA Today, 2 June 2025 Our bodies will release more cortisol as a defense mechanism. Audrey Noble, Vogue, 25 June 2025 Scientists say the bees' temperament is a defense mechanism to ward off predators. Rebecca Morin, USA Today, 24 June 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 10 Jul. 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

More from Merriam-Webster on defense mechanism

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