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 In March researchers at Imperial College London used a model to calculate the potential death toll of the virus, assuming that people and governments took no measures to stop its spread. The Economist, "Why relations between economists and epidemiologists have been testy," 14 Nov. 2020 Mueller said state officials will continue to analyze new information about the virus and consider what information is most useful in decisions about how schools should operate. Erin Golden, Star Tribune, "COVID-19 surge pushes more Minnesota schools to distance learning," 13 Nov. 2020 Yet Safdar warns that much still is unknown about the virus. Guy Boulton, Milwaukee Journal Sentinel, "'People in the community don't seem to care': Wisconsin hospitals' struggles with COVID surge isn't getting people to change behavior," 13 Nov. 2020 Cvitanovich, a medical doctor, was one who sounded early warning signs about the virus as Jefferson Parish cases raced out to the highest number in the state earlier in the pandemic. Faimon Roberts, NOLA.com, "Jefferson Parish Coroner, family test positive for coronavirus," 13 Nov. 2020 But there are still plenty of unanswered questions about the virus and the potential weapons to combat it. James Paton, Bloomberg.com, "When Will Covid Be Defeated? You’ll Need Patience: Coronavirus Q&A," 12 Nov. 2020 Even experts know so little about the virus at this point. Patrice Peck, Wired, "What Writing a Pandemic Newsletter Taught Me About America," 12 Nov. 2020 Defensive end Zachary Carter sat out the first week of preseason camp in August due to concerns about a virus that hospitalized his father and killed a close friend of the family. Edgar Thompson, orlandosentinel.com, "Gators stay vigilant, try to avoid SEC’s COVID-19 issues," 11 Nov. 2020 Frontline workers are sometimes invited on to talk about the virus, with the broadcast broken down into local dialects so everyone gets a clear understanding. Eoin Mcsweeney, CNN, "The pandemic reimagined sub-Saharan education, but access to digital is urgently needed," 10 Nov. 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 Tocharian 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

16 Nov 2020

Cite this Entry

“Virus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/virus. Accessed 25 Nov. 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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