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

Over the past couple of decades, research has shown how scratching taps into our brain’s reward and immune systems, producing a strange mix of pleasure and discomfort that makes it all but impossible to resist. —Cody Cottier, Discover Magazine, 19 July 2024

And, for good reason: Not only does a dry mouth signify a lack of fluids, but also that your immune system is becoming weakened. —Philipp Wehsack, Vogue, 18 July 2024

Interleukin inhibitors weaken the signal for the immune system to cause inflammation. —Phuoc Anh (anne) Nguyen, Pharmd, Ms, Verywell Health, 17 July 2024

The findings add a new wrinkle to the debate over whether the virus can cause long-lasting changes to the immune system or whether the body's defenses reset themselves following recovery. —Adriel Bettelheim, Axios, 17 July 2024

Word History

First Known Use

circa 1919, in the meaning defined above

Kids Definition

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, lymphocytes, and antibodies

Medical Definition

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), lymphocytes including the B cells and T cells, and antibodies