AIDS

noun

ˈādz How to pronounce AIDS (audio)
Synonyms of AIDSnext
: a disease of the human immune system that is characterized cytologically especially by reduction in the numbers of CD4-bearing helper T cells to 20 percent or less of normal thereby rendering the subject highly vulnerable to life-threatening conditions (such as Pneumocystis carinii pneumonia) and to some (such as Kaposi's sarcoma) that become life-threatening and that is caused by infection with HIV commonly transmitted in infected blood especially during illicit intravenous drug use and in bodily secretions (such as semen) during sexual intercourse

Examples of AIDS 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.
Pregnant people, those with AIDS or HIV and people under 110 pounds may not donate. — Eva Flowe july 30, Charlotte Observer, 30 July 2026 Newman and the team now cater to over 100 various illnesses, including cancer, HIV/AIDS and an array of mental health issues like PTSD and anxiety. — Lily Ford, HollywoodReporter, 29 July 2026 His later partnerships with AIDS activists and his push to accelerate experimental-drug trials for HIV helped transform the infection into a survivable condition. — Katherine J. Wu, The Atlantic, 28 July 2026 In 1986, Charleson, who was gay, was diagnosed with HIV and would die of AIDS four years later at age 40. — Brian Welk, IndieWire, 28 July 2026 See All Example Sentences for AIDS

Word History

Etymology

acquired immunodeficiency syndrome

First Known Use

1982, in the meaning defined above

Time Traveler
The first known use of AIDS was in 1982

Phrases Containing AIDS

Rhymes for AIDS

See All Rhymes for AIDS

Browse Nearby Words

aid/relief convoy
AIDS
AIDS-related complex
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Cite this Entry

“AIDS.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/AIDS. Accessed 2 Aug. 2026.

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Kids Definition

AIDS

noun
ˈādz How to pronounce AIDS (audio)
: a serious disease of the human immune system marked by destruction of a large proportion of the helper T cells in the body due to infection by the HIV virus commonly transmitted especially in blood and semen

Medical Definition

AIDS

noun
ˈādz How to pronounce AIDS (audio)
: a disease of the human immune system that is characterized cytologically especially by a reduction in the numbers of CD4-bearing helper T cells to 20 percent or less of normal thereby rendering the subject highly vulnerable to life-threatening conditions (as Pneumocystis carinii pneumonia) and to some that become life threatening (as Kaposi's sarcoma) and that is caused by infection with HIV commonly transmitted in infected blood especially during illicit intravenous drug use and in bodily secretions (as semen) during sexual intercourse

called also acquired immune deficiency syndrome, acquired immunodeficiency syndrome

More from Merriam-Webster on AIDS

Britannica.com: Encyclopedia article about AIDS

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