1
: either of two retroviruses (species Human immunodeficiency virus 1 and 2 of the genus Lentivirus) that infect and destroy helper T cells of the immune system and that when left untreated cause AIDS

Note: HIV retroviruses are transmitted through contact with blood, semen, rectal and vaginal fluids, or breast milk and typically cause flu-like symptoms during the acute phase of infection, but often cause few or no symptoms during the chronic phase of infection when treated with antiretroviral drugs.

… the longer people are infected with HIV and the more immune-deficient they become, the more readily they seem to pass HIV to others.Robert R. Redfield et al.
Years of careful research have proven beyond doubt that the HIV virus causes AIDS, that antiretroviral drug treatment saves lives, and that the drug nevirapine is safe and effective in preventing the spread of HIV from mothers to their babies.Richard Marlink et al.

called also AIDS virus, human immunodeficiency virus

compare hiv-1, hiv-2
2
: the infection or disease caused by HIV
Early symptoms of HIV develop in 50 to 90 percent of people who are infected, usually beginning two to four weeks after exposure. … Because the signs and symptoms of … HIV may be similar to other common illnesses, such as mononucleosis, most people do not initially realize that they have HIV.Paul E. Sax

Examples of HIV 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.
In fact, the United Nations has reported a steady decrease in new HIV infections in the country, with primary transmission occurring from heterosexual contact. Tess Foley-Cox, theweek, 7 Nov. 2024 His causes included fighting HIV and AIDS, educating children, and providing for the poor around the world. Hillel Italie, The Christian Science Monitor, 4 Nov. 2024 Questioning on multiple occasions whether HIV is really a cause or the only cause of AIDS as described by an article in the New York magazine. Bruce Y. Lee, Forbes, 2 Nov. 2024 In many ways, Pose, which dealt with a wide spectrum of issues, including HIV and death, helped Canals clearly communicate that to Brinson and, in turn, the audience. Ronda Racha Penrice, The Hollywood Reporter, 1 Nov. 2024 See all Example Sentences for HIV 

Word History

First Known Use

1986, in the meaning defined at sense 1

Time Traveler
The first known use of HIV was in 1986

Dictionary Entries Near HIV

Cite this Entry

“HIV.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/HIV. Accessed 24 Nov. 2024.

Kids Definition

: any of a group of viruses that infect and destroy helper T cells causing the marked reduction in their numbers that is diagnostic of AIDS

Medical Definition

1
: either of two retroviruses (species Human immunodeficiency virus 1 and 2 of the genus Lentivirus) that infect and destroy helper T cells of the immune system and that when left untreated cause AIDS

Note: HIV retroviruses are transmitted through contact with blood, semen, rectal and vaginal fluids, or breast milk and typically cause flu-like symptoms during the acute phase of infection, but often cause few or no symptoms during the chronic phase of infection when treated with antiretroviral drugs.

called also AIDS virus, human immunodeficiency virus

compare hiv-1, hiv-2
2
: the infection or disease caused by HIV
Last Updated: - Updated example sentences
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