AIDS

noun

: 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.
This will be the 27th of these events, which are produced by Broadway Cares/Equity Fights AIDS. Jane Levere, Forbes.com, 11 July 2025 Collins has expressed wanting to protect funding for PEPFAR, the George W. Bush-era program designed to fight the global spread of HIV and AIDS. Nick Mordowanec, MSNBC Newsweek, 11 July 2025 The State Department is reviewing funding from the United States President’s Emergency Plan for AIDS Relief, or PEPFAR, a spokesperson told NPR in June. Jordan Novet, CNBC, 11 July 2025 But representation in the Hong Kong media primarily took the form of the AIDS epidemic. Calista Oetama, Sacbee.com, 11 July 2025 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

Cite this Entry

“AIDS.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/AIDS. Accessed 15 Jul. 2025.

Kids Definition

AIDS

noun
: 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
: 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

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!