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
However, in some people—especially young children, older adults, or those with weakened immune systems—the infection can cause complications.
—
Brandi Jones, Health, 5 Oct. 2025
With sepsis, the immune system has an abnormal response to an infection — either too exuberant or too minimal.
—Dr. Marc Siegel , Melissa Rudy, FOXNews.com, 5 Oct. 2025
The fresh red bell peppers in this meal are packed with nutrients, especially vitamin C and A for the immune system and eye health.
—Susan Selasky, Freep.com, 4 Oct. 2025
The Basil Pesto Bowtie Salad and Smoked Mozzarella Penne Salad may be contaminated by bacteria listeria monocytogenes, which can cause fatal infections in children, the elderly and those with weakened immune systems, according to a news release from Kroger.
—Matthew Cupelli, Cincinnati Enquirer, 4 Oct. 2025
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Brandi Jones, Health, 5 Oct. 2025
With sepsis, the immune system has an abnormal response to an infection — either too exuberant or too minimal.
—Dr. Marc Siegel , Melissa Rudy, FOXNews.com, 5 Oct. 2025
The fresh red bell peppers in this meal are packed with nutrients, especially vitamin C and A for the immune system and eye health.
—Susan Selasky, Freep.com, 4 Oct. 2025
The Basil Pesto Bowtie Salad and Smoked Mozzarella Penne Salad may be contaminated by bacteria listeria monocytogenes, which can cause fatal infections in children, the elderly and those with weakened immune systems, according to a news release from Kroger.
—Matthew Cupelli, Cincinnati Enquirer, 4 Oct. 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 8 Oct. 2025.
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