immune system

American

noun

Anatomy.

a diffuse, complex network of interacting cells, cell products, and cell-forming tissues that protects the body from pathogens and other foreign substances, destroys infected and malignant cells, and removes cellular debris: the system includes the thymus, spleen, lymph nodes and lymph tissue, stem cells, white blood cells, antibodies, and lymphokines.

immune system Scientific

The body system in humans and other animals that protects the organism by distinguishing foreign tissue and neutralizing potentially pathogenic organisms or substances. The immune system includes organs such as the skin and mucous membranes, which provide an external barrier to infection, cells involved in the immune response, such as lymphocytes, and cell products such as lymphokines.
See also autoimmune disease immune response

immune system Cultural

The system in the body that works to ward off infection and disease. Central to this system are the white blood cells. Some white blood cells produce antibodies in response to specific antigens that may invade the body; others function as scavengers to fight infection by destroying bacteria and removing dead cells.

Etymology

Origin of immune system

First recorded in 1960–65

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

They act as messengers, telling our cells what to do, and play vital roles in our skin health, immune system and helping to control our hormones.

From BBC

T cells act as the immune system's memory, preserving instructions from past infections so the body can respond quickly in the future.

From Science Daily

This misinterpretation activates the cell's innate immune system, creating a false alarm that can lead to inflammation and disease.

From Science Daily

Whether due to spirit intervention or a strong immune system, little Charley recovered, and Maria took him back home to western New York.

From Literature

The researchers also observed notable alterations in immune system cells.

From Science Daily

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023