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 The antiviral drug Remdesivir does not appear to have a beneficial impact on coronavirus patients’ chances of survival, according to a study sponsored by the World Health Organization. Washington Post, "U.S. surpasses 64,000 new coronavirus infections for first time since late July," 16 Oct. 2020 In the course of the pandemic, thanks to better treatments such as antiviral drugs, steroids and convalescent plasma, our health care professionals have shortened the average hospital stay to right around eight days. Robert Gehrke, The Salt Lake Tribune, "Robert Gehrke: Utah’s worst coronavirus outbreak hasn’t peaked and everyone seems to have given up," 8 Oct. 2020 Despite Trump's upbeat talk about the disease, his own treatment has been far from typical, as his doctors rushed him onto experimental antiviral drugs and prescribed an aggressive course of steroids that would be unavailable to the average patient. Zeke Miller, Star Tribune, "Trump reports 'no symptoms,' returns to downplaying virus," 7 Oct. 2020 Over the weekend, Trump was airlifted to Walter Reed, in Bethesda, Md., where he was treated with experimental antibodies and antiviral drugs and prescribed an aggressive course of steroids. Catherine Ho,, "Health experts outraged by Trump’s response to contracting COVID-19," 6 Oct. 2020 Their discovery has also allowed for the rapid development of antiviral drugs directed at hepatitis C. Elizabeth Cooney, STAT, "Trio wins Nobel Prize in medicine for discovery of hepatitis C virus," 5 Oct. 2020 Trump was leaving the hospital after receiving a fourth dose of the antiviral drug remdesivir Monday evening, Conley said. Zeke Miller,, "Trump, back at the White House, compares COVID-19 to the flu: ‘We have learned to live with it’," 6 Oct. 2020 He was set to receive the fifth and final dose of the antiviral remdesivir Tuesday at the White House. Jill Colvin, Anchorage Daily News, "Trump, tweeting from White House, again falsely compares COVID-19 to seasonal flu," 6 Oct. 2020 Trump was leaving the hospital after receiving a fourth dose of the antiviral drug remdesivir Monday evening, Conley said. Zeke Miller, Star Tribune, "Trump, still infectious, back at White House — without mask," 6 Oct. 2020 Recent Examples on the Web: Noun People infected with Covid-19 generally go through an initial phase of infectivity that could be impacted by an antiviral. NBC News, "Massive WHO remdesivir study suggests no Covid-19 benefit. Doctors aren't so sure.," 16 Oct. 2020 Soon after arriving at the hospital Friday evening, Trump was given the first of five doses of remdesivir, an antiviral. USA Today, "Donald Trump's COVID-19 treatment is similar to the average American hospitalized with coronavirus. Only faster.," 6 Oct. 2020 Trump also is taking remdesivir, a repurposed antiviral that has received emergency use authorization from the FDA. Michael Greshko, National Geographic, "What President Trump’s emergency COVID-19 therapies say about his condition," 5 Oct. 2020 Remdesivir is also an antiviral and is already commonly used with dexamethasone, which tamps down the body’s immune response and is given later in the illness, when some patients’ immune systems go into overdrive and attack their vital organs. Katie Thomas, New York Times, "Use of Dexamethasone to Treat Trump Suggests Severe Covid-19, Experts Say," 4 Oct. 2020 Once in the hospital, patients can be treated with drugs to prevent the serious blood clots common in Covid-19, as well as a new antiviral and an old steroid. Helen Branswell, STAT, "As ‘the clock starts ticking’ after coronavirus infection, Trump faces an uncertain road ahead," 2 Oct. 2020 Monoclonal antibodies, if proven effective in large studies, could act as a sort of Tamiflu — an antiviral for influenza — but for the coronavirus. Catherine Ho,, "The experimental COVID drug Trump is taking right now is being tested in the Bay Area," 2 Oct. 2020 Roche is also studying the drug in combination with an antiviral. Thomas Mulier,, "Roche Drug Reduces Need for Ventilation in Covid Patients," 18 Sep. 2020 The trial looked at the impact of adding baricitinib, marketed as Olumiant, to treatment with remdesivir, an antiviral. Shari Rudavsky, The Indianapolis Star, "Lilly study shows its drug for rheumatoid arthritis helps in coronavirus treatment," 16 Sep. 2020

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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Time Traveler for antiviral

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The first known use of antiviral was in 1929

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Last Updated

21 Oct 2020

Cite this Entry

“Antiviral.” Dictionary, Merriam-Webster, Accessed 28 Oct. 2020.

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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

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