an·​ti·​vi·​ral | \ ˌan-tē-ˈvī-rəl How to pronounce antiviral (audio) , ˌan-tī-\

Definition of antiviral

 (Entry 1 of 2)

1 medical : acting, effective, or directed against viruses an antiviral vaccine/drug
2 : used to protect a computer from viruses : antivirus antiviral software



Definition of antiviral (Entry 2 of 2)

: an antiviral agent and especially a drug antivirals used in treating influenza

Examples of antiviral in a Sentence

Recent Examples on the Web: Adjective

An antiviral drug called remdesivir and another antibody treatment called ZMapp both inhibited the growth of the virus strain in human cells in laboratory studies, according to the paper published in the medical journal Lancet Infectious Diseases. Katie Hunt, CNN, "Experimental Ebola treatments effective in lab study," 9 July 2019 Louisiana will pay up to $58 million annually — or up to $290 million — for access to the generic form of the antiviral medication Epclusa, with a portion of the costs covered by federal dollars, according to the health department. Washington Post, "Louisiana reaches ‘Netflix-model’ deal to tackle hepatitis C," 26 June 2019 In addition, experimental antiviral drugs that can stop Ebola replication in its tracks are under development. Michael Greshko, National Geographic, "What is the Ebola virus, and can it be stopped?," 9 Apr. 2019 Viral infections usually stimulate the cells of their mammalian hosts to produce interferons, the signaling proteins that raise neighboring cells’ antiviral defenses and interfere with viral replication. Quanta Magazine, "Viruses Have a Secret, Altruistic Social Life," 15 Apr. 2019 The Calming Smelling Salts This small, gilded vial is filled with a reinvigorating mix of amethyst and Hawaiian black salts infused with a unique mix of antiviral lavender, patchouli, and peppermint oils designed to ward off germs—and bad energy! Lauren Valenti, Vogue, "How to Turn Your Desk Into the Ultimate Self-Care Station in 2019," 12 Dec. 2018 For genital herpes, you will most likely be prescribed an antiviral medication like Valacyclovir or Acyclovir. Hannah Orenstein, Seventeen, ""I Have a Cold Sore. Does That Mean I Have Herpes?"," 22 Feb. 2019 The pair played key roles transforming Gilead from a fledgling antiviral drugmaker into one of the world’s biggest pharmaceutical companies by sales, though a frequent target of criticism for the high prices of its HIV and hepatitis C drugs. Jonathan D. Rockoff, WSJ, "Gilead Sciences CEO Stepping Down," 25 July 2018 The best hope for that, at the moment, rests on a combination of vaccines to protect the uninfected and antiviral drugs to treat the infected, but the wrong mutation in the virus’ genome could render those weapons useless. Kiona N. Smith, Ars Technica, "Genghis Khan’s Mongol horde probably had rampant Hepatitis B," 11 May 2018

Recent Examples on the Web: Noun

There are already a few flu-fighting antivirals out there, the most widely known being Tamiflu (oseltamivir). Korin Miller, SELF, "What You Need to Know About Xofluza, the New Flu Medicine," 26 Oct. 2018 The patients are being treated at Jamaica Hospital Medical Center in Queens, including with antivirals, the CDC said. Betsy Mckay, WSJ, "Sick Emirates Passengers Test Positive For Common Viruses," 6 Sep. 2018 But certain people in high-risk groups — young children, pregnant women, people over age 65, people with other chronic diseases — may want to seek medical attention and antivirals like Tamiflu. Julia Belluz, Vox, "80,000 Americans died of the flu last year. Get your flu shot.," 27 Sep. 2018 The patients were treated with the flu vaccine and antivirals, reported the CDC in a statement. Rachel Becker, The Verge, "CDC investigates two more flights that landed with coughing passengers," 6 Sep. 2018 The experimental treatment can tackle various flu varieties such as H7N9 and H5N1, according to Genentech, and behaves in a different way from other antivirals. Sy Mukherjee, Fortune, "This New Single Dose Flu Drug Could Be Coming to the U.S. Before the Next Flu Season," 28 June 2018 The company, which is not abandoning research into tropical diseases such as malaria, is looking to license its early-stage products and stressed that its Sandoz generics unit continues to manufacture and sell antibiotics and antivirals. Ed Silverman, STAT, "Pharmalittle: Most drug price hikes occurred before Azar arrived; Novartis abandons antibiotics," 12 July 2018 There are antibiotics, including the powerful medication Ciprofloxacin, vaccines for smallpox and anthrax and antivirals for a deadly influenza pandemic. James Hohmann, Washington Post, "The Daily 202: Mick Mulvaney’s confession highlights the corrosive influence of money in politics," 25 Apr. 2018 But the development of more effective antivirals for people who have already been infected is a key element of fighting influenza, too. Sy Mukherjee, Fortune, "Brainstorm Health: 24 Hour Flu Killer, Scott Walker and Obamacare, Drug Regulation Under Trump," 23 Feb. 2018

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

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First Known Use of antiviral


1929, in the meaning defined at sense 1


1959, in the meaning defined above

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1 Aug 2019

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The first known use of antiviral was in 1929

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More Definitions for antiviral


an·​ti·​vi·​ral | \ -ˈvi-rəl How to pronounce antiviral (audio) \
variants: also antivirus \ -​rəs How to pronounce antivirus (audio) \

Medical Definition of antiviral

 (Entry 1 of 2)

: acting, effective, or directed against viruses antiviral drugs



Medical Definition of antiviral (Entry 2 of 2)

: an antiviral agent and especially a drug

More from Merriam-Webster on antiviral

Spanish Central: Translation of antiviral

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miscellaneous remnants or debris

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