virulent

adjective

vir·​u·​lent ˈvir-ə-lənt How to pronounce virulent (audio)
ˈvir-yə-
1
a
: marked by a rapid, severe, and destructive course
a virulent infection
b
: able to overcome bodily defensive mechanisms : markedly pathogenic
virulent bacteria
2
: extremely poisonous or venomous
3
: full of malice : malignant
virulent racists
4
: objectionably harsh or strong
virulent criticism
virulently adverb

Examples of virulent in a Sentence

The country seemed to be returning to the virulent nationalism of its past. the virulent look on her face warned me that she was about to say something unkind
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The researchers analyzed samples of coronary plaques–fatty buildups on artery walls–from heart patients and found that about 40% of them had virulent bacteria in them. Alex Knapp, Forbes.com, 29 Aug. 2025 The outlet reports that 14 more people were infected, bringing the number of people impacted by the virulent bacteria to 34 — the highest rate of infection in a decade. Cara Lynn Shultz, People.com, 28 Aug. 2025 The lives of just under 1,500 Lake County residents were lost to the virulent virus in 2020. Charles Selle, Chicago Tribune, 18 Aug. 2025 But filtration and sterilization is probably not perfect, risking infection of native aquatic species with virulent pathogens. Reader Commentary, Baltimore Sun, 10 Aug. 2025 See All Example Sentences for virulent

Word History

Etymology

Middle English, "discharging watery pus, purulent," borrowed from Latin vīrulentus "full of poison, venomous," from vīrus "venom, poisonous fluid" + -ulentus "having in quantity, full of" — more at virus

First Known Use

14th century, in the meaning defined at sense 1a

Time Traveler
The first known use of virulent was in the 14th century

Browse Nearby Words

Cite this Entry

“Virulent.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/virulent. Accessed 10 Sep. 2025.

Kids Definition

virulent

adjective
vir·​u·​lent ˈvir-(y)ə-lənt How to pronounce virulent (audio)
1
a
: marked by a rapid, severe, and often deadly course
a virulent infection
b
: able to overcome or break down the defenses of the body
a virulent germ
2
: extremely poisonous : noxious
3
: full of hate : spiteful
virulently adverb

Medical Definition

virulent

adjective
vir·​u·​lent -lənt How to pronounce virulent (audio)
1
a
: marked by a rapid, severe, and malignant course
a virulent infection
b
: able to overcome bodily defense mechanisms
a virulent pathogen
2
: extremely poisonous or venomous : noxious

More from Merriam-Webster on virulent

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