immune system

noun

|Updated on: 23 Jun 2018

Definition of immune system

: the bodily system that protects the body from foreign substances, cells, and tissues by producing the immune response and that includes especially the thymus, spleen, lymph nodes, special deposits of lymphoid tissue (as in the gastrointestinal tract and bone marrow), macrophages, lymphocytes including the B cells and T cells, and antibodies

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See immune system defined for kids

Recent Examples of immune system from the Web

Natural TdT does this to write millions of new variations of genes for antibodies, which the immune system can then select from to target invaders.

— robert f. service, Science | AAAS, "New technique could help scientists create a gene in just 1 day," 18 June 2018
Moreover, the immune system may be our enemy, not our friend.

— judith shulevitz, New York Times, "Is Our Obsession With Wellness Doing Us In?," 11 June 2018
If these peptides have enough irregularities, the immune system may identify them as problems and mark them for destruction.

— keridwen cornelius, Scientific American, "A Shot against Cancer Slated for Testing in Massive Dog Study," 7 June 2018
Immunology—her academic specialty—hinges on an essentially military metaphor of distinction between self and nonself: The immune system protects the homeland by destroying invaders.

— gabriel winant, The New Republic, "Barbara Ehrenreich’s radical critique of wellness and self-improvement," 23 May 2018
The nanoparticles showed the different types of tumor cells in every sample, how the immune system was reacting, and whether there were side effects.

— angela chen, The Verge, "How graphene and gold could help us test drugs and monitor cancer," 18 May 2018
Then, if the dog does later get cancer, the immune system will see it and go after it, Johnston said.

— rachel leingang, azcentral, "A cancer vaccine for dogs? ASU scientist hopes tests will lead to major breakthrough," 11 May 2018
Ozil’s immune system is a bit in trouble and I don’t know why.

— SI.com, "Arsenal Players 'Fed Up & Angry' With Teammate Following Series of Surprise Absences," 8 May 2018
And your brain calms everything down so that the immune system can go to work, and that’s what happens.

— stephanie nolasco, Fox News, "Cheech & Chong reflect on 'Up in Smoke' success: 'The studio had no idea what we were doing'," 2 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'immune system.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of immune system

circa 1919

in the meaning defined above

See Words from the same year

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IMMUNE SYSTEM Defined for English Language Learners

immune system

noun

Definition of immune system for English Language Learners

: the system that protects your body from diseases and infections

IMMUNE SYSTEM Defined for Kids

immune system

noun

Definition of immune system for Students

: the system of the body that fights infection and disease and that includes especially the white blood cells and antibodies and the organs that produce them

Medical Dictionary

immune system

noun

medical Definition of immune system

: the bodily system that protects the body from foreign substances, cells, and tissues by producing the immune response and that includes especially the thymus, spleen, lymph nodes, special deposits of lymphoid tissue (as in the gastrointestinal tract and bone marrow), lymphocytes including the B cells and T cells, and antibodies