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

Stress can also impact digestive functions and weakening the immune system to make individuals more prone to getting sick, eventually leading to long term health problems such, as heart disease high blood pressure and even stroke. —Jason Walker, Forbes, 28 Oct. 2024

In particular, vitamin C, which is abundant in kimchi, plays a key role in strengthening the immune system. —Maria Berentzen, Vogue, 28 Oct. 2024

Allergic reactions occur when a person's immune system is hypersensitive to a substance (allergen). —Daniel More, Health, 24 Oct. 2024

Consumption of food contaminated with listeria can lead to listeriosis, a serious infection that primarily affects adults 65 and older, people with weakened immune systems, pregnant women and newborns. —Andrea Chang, Los Angeles Times, 24 Oct. 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