immune system

noun

Updated on: 15 Apr 2018

Definition of immune system

: 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

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Recent Examples of immune system from the Web

Your mind, heart, endocrine system, and immune system are all affected, malfunctioning in ways both subtle and severe.

— wes judd, Outside Online, "What Happens to Your Body on No Sleep," 2 Apr. 2018
Scientists manipulated more than 20 genes related to the immune system, reproductive system, and development, revealing damaging effects on the insects.

— grace donnelly, Fortune, "Why We Can Learn a Lot From the Cockroach Genome About How to Adapt to Any Environment," 27 Mar. 2018
American cockroaches have more enzymes to break down toxins and stronger immune systems.

— sarah gibbens, National Geographic, "This Cockroach Can Survive Anywhere—Its DNA Proves It," 21 Mar. 2018
According to the World Health Organization, dioxins can cause liver damage, compromise the immune system, endocrine system and reproductive system, and chronic exposure can lead to cancer.

— stephen english, star-telegram, "Dangerous levels of toxins found in fish from Lake Worth, parts of the Trinity | Fort Worth Star-Telegram," 15 Mar. 2018
People most at-risk are children under age 5, people with weak immune systems and pregnant women.

— michelle miller, CBS News, "Two measles cases put U.S. travelers on high alert," 15 Mar. 2018
Some predisposing factors include Parkinson's, depression, diabetes, a weakened immune system, and obesity.

— mona gohara, Good Housekeeping, "7 Common Scalp Issues — And How to Treat Them," 13 Mar. 2018
To treat the cancer, Brown took chemotherapy and had two bone marrow transplants to replace the malignant cells in his blood and immune system.

— alice park, Time, "There Is No Cure for HIV—But Scientists May Be Getting Closer," 8 Mar. 2018
Asthma, chronic lung disease, blood disorders, endocrine, neurological conditions, kidney and liver disorders, heart disease and a weakened immune system are among the health issues that can make the flu more serious.

— justin madden, cleveland.com, "Flu-related deaths reach 21 in Cuyahoga County," 8 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'immune system.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of immune system

circa 1919

in the meaning defined above

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IMMUNE SYSTEM Defined for English Language Learners

immune system

noun

Definition of immune system for English Language Learners

: the system that protects your body from diseases and infections

IMMUNE SYSTEM Defined for Kids

immune system

noun

Definition of immune system for Students

: the system of the body that fights infection and disease and that includes especially the white blood cells and antibodies and the organs that produce them

Medical Dictionary

immune system

noun

medical Definition of immune system

: 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

Learn More about immune system

Spanish Central: Translation of immune system Nglish: Translation of immune system for Spanish speakers Britannica English: Translation of immune system for Arabic speakers Britannica.com: Encyclopedia article about immune system

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immune system

Definition of immune system

Recent Examples of immune system from the Web

First Known Use of immune system

IMMUNE SYSTEM Defined for English Language Learners

immune system

Definition of immune system for English Language Learners

IMMUNE SYSTEM Defined for Kids

immune system

Definition of immune system for Students

Medical Dictionary

immune system

medical Definition of immune system

Learn More about immune system

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immune system

Definition of immune system

Recent Examples of immune system from the Web

First Known Use of immune system

IMMUNE SYSTEM Defined for English Language Learners

immune system

Definition of immune system for English Language Learners

IMMUNE SYSTEM Defined for Kids

immune system

Definition of immune system for Students

Medical Dictionary

immune system

medical Definition of immune system

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