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immunodeficiency

noun

im·​mu·​no·​de·​fi·​cien·​cy ˌi-myə-nō-di-ˈfi-shən(t)-sē How to pronounce immunodeficiency (audio)
i-ˌmyü-nō-
: inability to produce a normal complement of antibodies or immunologically sensitized T cells especially in response to specific antigens
immunodeficient adjective

Examples of immunodeficiency in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Her 11-year-old daughter suffers from a rare immunodeficiency disorder that requires biweekly plasma infusions to provide some protection against disease. Joseph Choi, The Hill, 5 Nov. 2025 Risk factors for becoming ill include significant underlying medical conditions such as chronic lung disease, kidney disease, diabetes, cancer and immunodeficiency. Katia Hetter, CNN Money, 4 Sep. 2025 Tucked away in cat room at the Ohio Society for the Prevention of Cruelty to Animals (SPCA) and Humane Society in Lima, Dude waits patiently for a home — despite the fact that he’s been diagnosed with a common immune deficiency called feline immunodeficiency virus (FIV). Tj MacIas, Kansas City Star, 15 Apr. 2025 Pace said many of the cats are suffering from upper respiratory infections, eye infections and feline leukemia virus or feline immunodeficiency virus. Sean Krofssik, Hartford Courant, 3 Apr. 2025 See All Example Sentences for immunodeficiency

Word History

Etymology

immuno- + deficiency

First Known Use

1969, in the meaning defined above

Time Traveler
The first known use of immunodeficiency was in 1969

Browse Nearby Words

Cite this Entry

“Immunodeficiency.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/immunodeficiency. Accessed 29 Nov. 2025.

Kids Definition

immunodeficiency

noun
im·​mu·​no·​de·​fi·​cien·​cy -də-ˈfish-ən-sē How to pronounce immunodeficiency (audio)
: inability to produce the normal number of antibodies or T cells capable of acting in an immune system

Medical Definition

immunodeficiency

noun
im·​mu·​no·​de·​fi·​cien·​cy -di-ˈfish-ən-sē How to pronounce immunodeficiency (audio)
plural immunodeficiencies
: inability to produce a normal complement of antibodies or immunologically sensitized T cells especially in response to specific antigens see aids
immunodeficient adjective

More from Merriam-Webster on immunodeficiency

Last Updated: - Updated example sentences
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