immune system

American  

noun

Anatomy.

1. 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.

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immune system Scientific  

1. 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.

2. See also autoimmune disease immune response

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immune system Cultural  

1. 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.

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Etymology

Origin of immune system

First recorded in 1960–65

Example Sentences

The findings suggest a potential new target for treating age-related disorders of the blood and immune system.

From Science Daily

When a lone professor voiced a dissenting view, the school reacted in the manner of an immune system greeting a foreign pathogen.

From The Wall Street Journal

As people get older, the immune system often becomes less effective.

From Science Daily

The altered microbiota included higher levels of flagellated bacteria, which are known to activate the immune system and promote inflammation.

From Science Daily

It has the world’s best-selling drug, called Keytruda, which helps the immune system attack cancer cells, and launched more than a decade ago.

From Barron's