immune system
noun
: 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
Examples of immune system in a Sentence
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The hormone also helps to regulate blood pressure, blood sugar and the sleep-wake cycle, and can also help to bolster the immune system, according to health experts.
—
Amy McGorry, FOXNews.com, 14 Sep. 2025
Plus, that whole waning immunity thing means that your immune system needs to be periodically reminded that the SARS-Cov-2 is a bad thing.
—Bruce Y. Lee, Forbes.com, 14 Sep. 2025
As the immune system fights the infection, the tissues in the urinary tract become inflamed.
—Mark Gurarie, Health, 13 Sep. 2025
When our bodies digest protein in food, it gets broken down into amino acids, which have a hand in many bodily processes, such as building and preserving muscle, making hormones, boosting the immune system and even maintaining healthy hair, skin and nails.
—Jacqueline Howard, CNN Money, 12 Sep. 2025
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Amy McGorry, FOXNews.com, 14 Sep. 2025
Plus, that whole waning immunity thing means that your immune system needs to be periodically reminded that the SARS-Cov-2 is a bad thing.
—Bruce Y. Lee, Forbes.com, 14 Sep. 2025
As the immune system fights the infection, the tissues in the urinary tract become inflamed.
—Mark Gurarie, Health, 13 Sep. 2025
When our bodies digest protein in food, it gets broken down into amino acids, which have a hand in many bodily processes, such as building and preserving muscle, making hormones, boosting the immune system and even maintaining healthy hair, skin and nails.
—Jacqueline Howard, CNN Money, 12 Sep. 2025
See All Example Sentences for immune system
Cite this Entry
“Immune system.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/immune%20system. Accessed 16 Sep. 2025.
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