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
Recent Examples on the Web
When this happens, the immune system doesn't generate protective antibodies against the bacterium, and inflammation ratchets up.
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ArsTechnica, 11 July 2025
Several people raised their hands Wednesday to say recent surgeries and other health problems had left them with weak immune systems.
—Blake Nelson, San Diego Union-Tribune, 10 July 2025
Multiple exposures to the SARS-CoV-2 spike proteins via either vaccination or natural infection have helped our immune systems go around block, so to speak, quite a few times.
—Bruce Y. Lee, Forbes.com, 8 July 2025
Anti-inflammatory properties: Taking spirulina reduces inflammation (immune system activity), which may help with allergy symptoms.
—Mark Gurarie, Verywell Health, 8 July 2025
See All Example Sentences for immune system
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ArsTechnica, 11 July 2025
Several people raised their hands Wednesday to say recent surgeries and other health problems had left them with weak immune systems.
—Blake Nelson, San Diego Union-Tribune, 10 July 2025
Multiple exposures to the SARS-CoV-2 spike proteins via either vaccination or natural infection have helped our immune systems go around block, so to speak, quite a few times.
—Bruce Y. Lee, Forbes.com, 8 July 2025
Anti-inflammatory properties: Taking spirulina reduces inflammation (immune system activity), which may help with allergy symptoms.
—Mark Gurarie, Verywell Health, 8 July 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 21 Jul. 2025.
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