vir·​u·​lence | \ˈvir-ə-lən(t)s, ˈvir-yə- \

Definition of virulence 

: the quality or state of being virulent: such as

a : extreme bitterness or malignity of temper : rancor

b : malignancy, venomousness the virulence of a disease

c : the relative capacity of a pathogen to overcome body defenses

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Examples of virulence in a Sentence

I was surprised by the virulence of the criticism.

Recent Examples on the Web

Recent academic research has focused on how well peacekeepers do at reducing conflicts’ virulence and spread. Brandon Prins, Washington Post, "Armed peacekeepers really do protect civilians — with one big exception," 14 June 2018 Our research on the pharmaceutical industry has revealed that one reason for malaria’s continued virulence in the developing world is ineffective medicine. Smithsonian, "Are Fake Drugs The Reason Malaria Sickens Millions a Year?," 24 Apr. 2018 Bacteria rely on what researchers term virulence factors: molecules that aid their survival while undermining your immune system. Scientific American, "Why Are Some E. Coli Strains Deadly While Others Live Peacefully in Our Bodies?," 24 Apr. 2018 In this story, the South was a place apart, different from the rest of the country in the virulence of its white supremacy. Alexis C. Madrigal, The Atlantic, "When the Revolution Was Televised," 1 Apr. 2018 This reduces the disease’s virulence, presumably benefiting the health of those who carry the trait. Bradley J. Fikes,, "New and common malaria resistance trait identified in Scripps Research-led study," 22 Mar. 2018 The virulence of the response to what Texas and other red states saw as irresponsible, unconstitutional, overreach by the Obama administration and Democrats in Congress was something to behold. Chris Stirewalt, Fox News, "Trump triangulates early," 9 Mar. 2018 The virus constantly mutates and each different strain could have different transmissibility and different virulence from year to year. Jason Daley, Smithsonian, "Simply Exhaling May Spread Flu," 23 Jan. 2018 That’s in part because there are so many strains, and the virus is prone to mutations that change its virulence and transmissibility. Maggie Fox, NBC News, "Influenza might be spread simply by breathing, study finds," 19 Jan. 2018

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

1617, in the meaning defined above

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Time Traveler for virulence

The first known use of virulence was in 1617

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vir·​u·​lence | \ˈvir-(y)ə-lən(t)s \

Medical Definition of virulence 

: the quality or state of being virulent: as

a : relative severity and malignancy ameliorate the virulence of a disease

b : the relative capacity of a pathogen to overcome body defenses — compare infectivity

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Comments on virulence

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to clear from alleged fault or guilt

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