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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Minor gastrointestinal discomfort is probably the most common symptom; however, pathogens that may cause only minor sickness in some people may cause serious conditions or death in others, especially in the very young, old, or those with weakened immune systems.
—
Jalen Williams, Freep.com, 25 July 2025
When disturbed, the fungus releases spores that can cause severe respiratory infections, particularly in people with weakened immune systems.
—Justin Stebbing, JSTOR Daily, 24 July 2025
High risk groups include: Older adults People with weakened immune systems
Pregnant women
Those with underlying health conditions, such as asthma and heart disease
Getting a shot is especially important, Levy said, for those who haven’t had one in over a year and whose immunity has likely waned.
—Shreya Srinivasan, NBC news, 23 July 2025
People older than age 60 and those with weakened immune systems are more likely to get seriously sick, the California Department of Public Health warns.
—Molly Gibbs, Mercury News, 22 July 2025
See All Example Sentences for immune system
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Jalen Williams, Freep.com, 25 July 2025
When disturbed, the fungus releases spores that can cause severe respiratory infections, particularly in people with weakened immune systems.
—Justin Stebbing, JSTOR Daily, 24 July 2025
High risk groups include: Older adults People with weakened immune systems
Pregnant women
Those with underlying health conditions, such as asthma and heart disease
Getting a shot is especially important, Levy said, for those who haven’t had one in over a year and whose immunity has likely waned.
—Shreya Srinivasan, NBC news, 23 July 2025
People older than age 60 and those with weakened immune systems are more likely to get seriously sick, the California Department of Public Health warns.
—Molly Gibbs, Mercury News, 22 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 29 Jul. 2025.
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