Definition of virulent in English:



  • 1(of a disease or poison) extremely severe or harmful in its effects.

    ‘a virulent strain of influenza’
    ‘the poison is so virulent that it kills a fish instantly’
    • ‘Mark Oliver Everett is what epidemiologists and Dustin Hoffman call a hot spot, a highly contagious carrier of an extremely virulent disease who infects anyone who crosses his path.’
    • ‘The court and all those able to move into the countryside prudently did so, as the disease was less virulent there.’
    • ‘Their research can help head off not only the Nipah but also other virulent diseases that break out suddenly to plague man and beast.’
    • ‘And on the nursing front, Alwin notes that there's been an outbreak of atypical pneumonias in Asia, possibly harbingers of a more virulent flu strain to come.’
    • ‘When the next human ship came the native's story of a virulent disease fatal to humans was duly noted and dispatched back to the nearest Military outpost along with the recording from the satellite.’
    • ‘Violence and gamesmanship are a virulent virus infecting sport.’
    • ‘Unless there was an extremely virulent strain of influenza going around, it might not be worth the risk.’
    • ‘A preliminary investigation found that the symptoms displayed by the victims were similar to those caused by a virulent poison used to kill rats.’
    • ‘Five to 15 days after exposure a pneumonia that is not very different from other less virulent pneumonias acquired in the community (outside a hospital) develops.’
    • ‘36 patients in five Montreal hospitals have died from a virulent infection, officials confirmed Friday.’
    • ‘The herpes virus can be virulent, but you'll be surprised to learn that a garden herb can beat the symptoms into submission.’
    • ‘Both pack a virulent poison in their dorsal spines, so you must not touch anything, even what appears to be a rock, while diving.’
    • ‘This method, the inoculation of material containing the living organism, itself was not foolproof, since it was not possible to ensure a mild rather than a virulent infection, which might prove fatal.’
    • ‘There is no question that the outbreak of SARS (severe acute respiratory syndrome) has focused the world's attention on the dangers of how easily a virulent disease can spread around the globe.’
    • ‘Chinese health officials say that the strain is extremely virulent and killed one farmer in as little as two hours.’
    • ‘But the episode reveals how far this virulent disease has spread through the body corporate.’
    • ‘An understanding of the genetic makeup of the most virulent influenza strain ever seen could help health officials manage possible pandemics in the future.’
    • ‘Not every fever or cough is likely to be this virulent pneumonia.’
    • ‘And so massive amounts of radioactivity spewed out in an invisible cloud which spread the most virulent poison all over the land.’
    • ‘One little sip of this antidote would have rendered the most virulent poisons of the Borgias innocuous.’
    • ‘Here is a woman who is trying to defeat a horribly virulent disease in rice, one that destroys millions of acres in Asia, and she's using molecular techniques to do it.’
    • ‘However, it can produce a virulent poison called verotoxin, which attacks organs such as the kidneys.’
    poisonous, toxic, venomous, noxious, deadly, lethal, fatal, mortal, terminal, death-dealing, life-threatening, dangerous, harmful, injurious, pernicious, damaging, destructive, unsafe
    highly infectious, highly infective, highly contagious, infectious, infective, contagious, rapidly spreading, communicable, transmittable, transmissible, spreading, malignant, uncontrollable, pernicious, pestilential
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    1. 1.1 (of a pathogen, especially a virus) highly infective.
      ‘Staphylococcus aureus is a common organism whose virulent strains are causing problems’
      • ‘They also question whether terrorists would even try to develop West Nile as a weapon when more virulent viruses are available.’
      • ‘They're seem to spread like a virulent disease.’
      • ‘When a predisposing factor cannot be identified, potential explanations include a particularly virulent pathogen or an underlying genetic predisposition.’
      • ‘Malaria, introduced after 1650, became the Chesapeake's most virulent pathogen.’
      • ‘I have been a virologist, and in fact I think I was the first to do any genetic work with animal viruses, and I'm very, very aware of the potential dangers if virulent viruses acting on human beings are being worked with.’
      • ‘He said that this disease is virulent enough to kill all of the birds in a short period of time.’
      • ‘Of course, in such enclosed confines, virulent viruses can run wild, and if the person next to you is sniffling, find another seat if you can.’
      • ‘By comparison, six out of seven unvaccinated animals had to be treated for virulent malaria.’
      • ‘On the last days, I inoculated Joseph Meister with the most virulent virus of rabies.’
      • ‘It sparked a diplomatic incident when the ill-fated ship docked in Gibraltar leading to Spain closing its border with the Rock to ensure the virulent virus did not spread.’
      • ‘The virus is particularly virulent for humans, horses, and gamebirds.’
      • ‘Concerning biotic stress, plants exposed to virulent and avirulent pathogens respond with a range of defence- and damage-limiting mechanisms.’
      • ‘It's sobering news that a virulent pathogen can evolve so quickly.’
      • ‘Such systemic immunity provides the plant with an effective state of acquired resistance throughout its different organs against subsequent attack by a broad spectrum of virulent pathogens.’
      • ‘Labs are rated on a scale of one to four, four being the highest level of containment where the nastiest, most virulent pathogens are handled.’
      • ‘Dr. Mackinnon said: ‘How does immune selection create more virulent pathogens?’’
      • ‘The paper reflects a major step forward in the study of how some of the world's most virulent viruses, such as West Nile, SARS, Ebola and Hepatitis C interact with their hosts.’
      • ‘Bijerinck disproved this theory when he showed that the sap could successively transmit the fully virulent disease through a large number of plant generations.’
      • ‘So you can see that this was an exceptionally virulent virus.’
      • ‘This intense thriller follows the survivors of a deadly and virulent virus which wipes out London and possibly most of the world.’
  • 2Bitterly hostile.

    ‘a virulent attack on liberalism’
    • ‘You know, I think you have to take a good look at this virulent attack by Barbara.’
    • ‘In speaking to Nazi friends, I've reproached them for the virulent anti-Semitism in their societies.’
    • ‘The Washington Times and the Unification Church's Insight were among the more virulent attackers of Bill Clinton.’
    • ‘For many, the combination of virulent radicalism and reasoned temperament is wholly seductive, and attacks upon Chomsky by conservatives and centrists have only granted him a martyr's aura.’
    • ‘E. A. Freeman's virulent attacks on J. A. Froude for inadequacy in using archives are similarly to be recognized as rhetoric.’
    • ‘His supporters also launched a virulent attack on Kemp.’
    • ‘Hitler's anti-Semitism, virulent nationalism, and antisocialism were simply more extreme than those shared by earlier German leaders and ‘ordinary Germans’.’
    • ‘The more virulent attacks come from Western intellectuals.’
    • ‘The deal was struck after days of virulent attack and counter attack.’
    • ‘When word came that Iron Mike had been floored by a virulent attack of the sniffles, his disconsolate well-wishers had to shuffle off without meeting their thick-necked hero.’
    • ‘It becomes more obvious that the options the two Parties present to the electorate, offer the unenviable choice between a raging toothache, a migraine, and a virulent attack of the Farmer's.’
    • ‘Ultimately this defense was transmogrified into a virulent attack on the Danish State Lutheran Church.’
    • ‘What surprised me most about that election year was the amazingly virulent attacks on Gore from the left.’
    • ‘Bhisham Sahni's ‘Saag Meat’ is a gentle but virulent attack on the hypocrisy that affluent middle class India continues to live its life with.’
    • ‘If you weren't contaminated before, you'll be in close contact with long-lived virulent nasties soon's you handle one of those magazines.’
    • ‘Over the years, founder Ted Byfield has been particularly virulent in his attacks on the mindset that is increasingly reliant on government handouts and regulation.’
    • ‘Ezra Pound's virulent anti-Semitism, his radio broadcasts and tracts in support of Mussolini, stand as potent reminders of the limits and dangers of the human imagination.’
    • ‘They try, judge and convict individuals who cannot defend themselves from such virulent attacks.’
    • ‘Mr Duncan Smith launched his most virulent attack yet on the suspected plotters in an article in The Spectator in which he acknowledged some in the party were convinced he should not be leader.’
    • ‘This work thus presages the more virulent attack on the German socialists to be found in the Communist Manifesto, produced two years later.’
    vitriolic, malicious, malevolent, malignant, malign, evil-intentioned, resentful, hostile, spiteful, venomous, vicious, vindictive, bitter, rancorous, acrimonious, mordant, astringent, incisive, cutting, biting, scathing, caustic, stinging, blistering, searing, withering, abusive, mean, nasty, aggressive, savage, harsh, devastating
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Late Middle English (originally describing a poisoned wound): from Latin virulentus, from virus ‘poison’ (see virus).