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 The researchers’ study of dice snakes has prompted further questions from other scientists, such as whether life experience can explain why some individual snakes don’t engage in all three defense mechanisms. Christian Thorsberg, Smithsonian Magazine, 9 May 2024 As a defense mechanism, ladybugs secrete a substance that can cause painful mouth and stomach ulcers, Watkins says. Clare Mulroy, USA TODAY, 9 May 2024 This work lends support to a longstanding theory that — because the chemical reaction underlying bioluminescence uses up oxygen — bioluminescence first evolved as a defense mechanism against the production of dangerous oxygen-containing molecules called free radicals. Sam Jones, New York Times, 23 Apr. 2024 Research has found that radishes help enhance the body's antioxidant defense mechanism and positively impact changes in blood glucose (sugar) levels. Cynthia Sass, Mph, Health, 13 Apr. 2024 See all Example Sentences for defense mechanism 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'defense mechanism.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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

Dictionary Entries Near defense mechanism

Cite this Entry

“Defense mechanism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/defense%20mechanism. Accessed 19 Jun. 2024.

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

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!