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autoimmune

adjective

au·​to·​im·​mune ˌȯ-tō-im-ˈyün How to pronounce autoimmune (audio)
: of, relating to, or caused by autoantibodies or T cells that attack molecules, cells, or tissues of the organism producing them
autoimmune diseases
autoimmunity noun
autoimmunization noun

Did you know?

Any healthy body produces a variety of antibodies, proteins in the blood whose job is to protect the body from unwanted bacteria, viruses, and cancer cells. The cells and organs that deal with such infections make up the immune system. In some people and animals, for various reasons, the antibodies become overactive and turn on the body's healthy tissues as well; the result is an autoimmune disease—an immune response directed against one's own self. More than eighty autoimmune diseases have been identified, the best-known being type 1 diabetes, multiple sclerosis, lupus, and rheumatoid arthritis.

Examples of autoimmune in a Sentence

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.
Fights Inflammation Inflammation is a part of the process of many different diseases, including heart disease, arthritis, autoimmune disorders, and cancer. Heidi Moawad, Verywell Health, 1 Dec. 2025 People with celiac disease, a hereditary autoimmune disorder, have to eat a gluten-free diet. Katie Akin, Southern Living, 28 Nov. 2025 The clinical stage biotech business develops treatments for autoimmune and inflammatory diseases. Hang Nguyen, San Diego Union-Tribune, 27 Nov. 2025 That means people [going] through chemo or who have autoimmune diseases, and health issues like that can use them. Gillian Telling, PEOPLE, 25 Nov. 2025 See All Example Sentences for autoimmune

Word History

Etymology

auto- + immune, after autoimmunity, borrowed from French auto-immunité

First Known Use

1952, in the meaning defined above

Time Traveler
The first known use of autoimmune was in 1952

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Cite this Entry

“Autoimmune.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/autoimmune. Accessed 3 Dec. 2025.

Kids Definition

autoimmune

adjective
au·​to·​im·​mune ˌȯt-ō-im-ˈyün How to pronounce autoimmune (audio)
: relating to or caused by an abnormal condition in which an organism's immune system attacks and destroys parts of its own cells or tissues
multiple sclerosis is an autoimmune disease

Medical Definition

autoimmune

adjective
au·​to·​im·​mune -im-ˈyün How to pronounce autoimmune (audio)
: of, relating to, or caused by antibodies or T cells that attack molecules, cells, or tissues of the organism producing them
autoimmune diseases
Last Updated: - Updated example sentences
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