virus

noun
vi·​rus | \ ˈvī-rəs How to pronounce virus (audio) \
plural viruses

Definition of virus

1a : any of a large group of submicroscopic infectious agents that are usually regarded as nonliving extremely complex molecules, that typically contain a protein coat surrounding an RNA or DNA core of genetic material but no semipermeable membrane, that are capable of growth and multiplication only in living cells, and that cause various important diseases in humans, animals, and plants also : filterable virus
b : a disease or illness caused by a virus
c : the causative agent of an infectious disease
2 : something that poisons the mind or soul the force of this virus of prejudice— V. S. Waters
3 : a computer program that is usually disguised as an innocuous program or file, that often produces copies of itself and inserts them into other programs, and that when run usually performs a malicious action (such as destroying data or damaging software)
4 archaic : venom sense 1

Examples of virus in a Sentence

Is the illness caused by bacteria or a virus? I think I have the virus that's going around this winter. The software checks your hard drive for viruses.
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Recent Examples on the Web The appeal in each case isn’t just the element of surprise, or the proximity to outdoor space and fresh air in these virus-wary times. John King, SFChronicle.com, "On Nob Hill and in Mission Bay, two new housing projects serve much different needs," 9 Aug. 2020 For much of the pandemic, testing did not keep up with the virus' spread, but the state recently has worked to expand testing and reduce results turnaround time, which had been up to two weeks or longer for some tests. Chelsea Curtis, The Arizona Republic, "Arizona reports 13 new known COVID-19 deaths, 816 new cases as hospitalizations continue to drop," 9 Aug. 2020 But as the virus and office shutdowns linger on, homebuyers are now driving up prices in those second-home markets. Lance Lambert, Fortune, "Second-home prices soar in Aspen and Martha’s Vineyard as the affluent flee megacities," 9 Aug. 2020 Davie said a plan to interview officers was derailed once the pandemic tightened its grip on the city and the police department, with many officers calling in sick after contracting the virus. Mark Morales, CNN, "Lawsuit over NYPD discipline records highlights the tension between police and oversight agencies," 9 Aug. 2020 About half of licensed child care centers across the nation could end up permanently closing because of the virus. Melissa Fletcher Stoeltje, ExpressNews.com, "The coronavirus means San Antonio parents have to make choices this fall — and some have more options than others," 9 Aug. 2020 The emphasis on student behavior is part of a broader effort to create safe bubbles on campus even if the virus surges elsewhere. Michael Hill, Star Tribune, "No parties, no trips: Colleges set COVID-19 rules for fall," 9 Aug. 2020 Classes are only being held online until cases of the virus decline, schools officials have said. The Salt Lake Tribune, "Here’s a breakdown of how some of the biggest school districts in Utah plan to reopen," 9 Aug. 2020 With no deal on virus relief in sight, lawmakers went home on Friday with instructions to be ready to return for a vote on an agreement. Jonathan Lemire And Zeke Miller, chicagotribune.com, "Coronavirus aid updates: Trump’s attempt to bypass Congress likely to be met with legal challenges," 9 Aug. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'virus.' 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 virus

1599, in the meaning defined at sense 4

History and Etymology for virus

Middle English, "pus, discharge from a sore, semen," borrowed from Latin vīrus (neuter) "venom, poisonous fluid, acrid element in a substance, secretion with medical or magical properties," going back to an Indo-European base *u̯is-/*u̯īs- "poison, venom," whence also Middle Irish "venom, poison, evil," Greek īós "poison," Tocharian A wäs and Tocharhian B wase, Sanskrit viṣáṃ, Avestan viš, viša- (also vīš?); (sense 1) borrowed from German, borrowed from Latin

Note: The application of Latin vīrus to the submicroscopic infectious agents now considered viruses (rather than to any infectious agent) was apparently first made by the Dutch microbiologist Martinus Beijerinck (1851-1931) in "Ueber ein Contagium vivum fluidum als Ursache der Fleckenkrankheit der Tabaksblätter," Verhandelingen der Koninklijke Akademie van Wetenschappen te Amsterdam, Tweede Sectie, Deel VI, no. 5 (1898). Beijerinck, in studying tobacco mosaic virus, mistakenly believed that the agent was a fluid (contagium vivum fluidum, "living fluid infection") because it passed through filters capable of trapping bacteria. — The neuter gender of vīrus suggests that it was originally an s-stem; forms in text other than the nominative and accusative are perhaps found only in Lucretius. The length of the vowel in Latin, Irish, and Greek, in contrast to the short vowel in Tocharian and Indo-Iranian, has been variously accounted for. M. Mayrhofer (Etymologisches Wörterbuch des Altindoarischen) suggests that the etymon was originally a root noun, *u̯īs, *u̯is-ó-, with lengthening of the monosyllabic vowel; the daughter languages then generalized one or the other form.

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Time Traveler for virus

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The first known use of virus was in 1599

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Last Updated

12 Aug 2020

Cite this Entry

“Virus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/virus. Accessed 15 Aug. 2020.

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More Definitions for virus

virus

noun
vi·​rus | \ ˈvī-rəs How to pronounce virus (audio) \

Kids Definition of virus

1 : a disease-causing agent that is too tiny to be seen by the ordinary microscope, that may be a living organism or may be a very special kind of protein molecule, and that can only multiply when inside the cell of an organism
2 : a disease caused by a virus
3 : a usually hidden computer program that causes harm by making copies of itself and inserting them into other programs

virus

noun
vi·​rus | \ ˈvī-rəs How to pronounce virus (audio) \

Medical Definition of virus

1a : the causative agent of an infectious disease
b : any of a large group of submicroscopic, infectious agents that are usually regarded as nonliving, extremely complex molecules or sometimes as very simple microorganisms, that typically contain a protein coat surrounding an RNA or DNA core of genetic material but no semipermeable membrane, that are capable of growth and multiplication only in living cells, and that cause various important diseases in humans, animals, and plants also : filterable virus
c : a disease caused by a virus
2 : an antigenic but not infectious material (as vaccine lymph) obtainable from a case of an infectious disease

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