influenza

noun
in·​flu·​en·​za | \ ˌin-(ˌ)flü-ˈen-zə How to pronounce influenza (audio) \

Definition of influenza

1a : an acute, highly contagious, respiratory disease caused by any of three orthomyxoviruses:
(1) or influenza A : moderate to severe influenza that in humans is marked especially by sudden onset, fever, sore throat, fatigue, muscle aches, inflammation of the respiratory mucous membranes, and cough, that has numerous variants caused by subtypes (such as H1N1, H2N2, or H3N2) of an orthomyxovirus (species Influenza A virus of the genus Influenzavirus A) infecting humans and various animals (such as birds or pigs), and that may occur in seasonal epidemics or sometimes pandemics following mutation in the causative virus
(2) or influenza B : influenza with less severe symptoms that is caused by an orthomyxovirus (species Influenza B virus of the genus Influenzavirus B) infecting only humans and especially children and that may occur in seasonal epidemics but not pandemics
(3) or influenza C : mild influenza that is often asymptomatic, is caused by an orthomyxovirus (species Influenza C virus of the genus Influenzavirus C) infecting only humans, and does not occur in epidemics or pandemics
b : any of various human respiratory infections of undetermined cause not used technically
2 : any of various virus diseases of domestic animals marked especially by fever, respiratory symptoms, and inflammation of mucous membranes

Note: All types of influenza are commonly called "the flu."

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Other Words from influenza

influenzal \ ˌin-​(ˌ)flü-​ˈen-​zəl How to pronounce influenzal (audio) \ adjective
influenzal pneumonia influenzal symptoms

Examples of influenza in a Sentence

Recent Examples on the Web

There's the potential to be trapped with thousands of people, any of whom could be suffering from norovirus and E. coli, influenza, chickenpox or, as a recent Scientology cruise demonstrated, measles. NBC News, "Trump dismisses economic slowdown fears: Read the Morning Rundown," 19 Aug. 2019 The reports involve different regions of the state and different diseases, including pertussis (whooping cough), influenza, haemophilus influenzae infection, Legionnaire’s disease and pneumonia caused by rhinovirus or human metapneumovirus. USA TODAY, "Titanic auction, Legos, mighty Mississippi: News from around our 50 states," 22 July 2019 Only four such declarations have been made in the past: in 2009, for pandemic influenza; in 2014, for a polio resurgence in several countries; in 2014, for the Ebola epidemic in West Africa; and in 2016, for the Zika virus epidemic. Denise Grady, New York Times, "Ebola Outbreak in Congo Is Declared a Global Health Emergency," 17 July 2019 In 1901, Harrison fell ill with influenza and did not recover. Dawn Mitchell, Indianapolis Star, "Dillinger, Dean and more: 12 famous graves in Indiana," 7 Aug. 2019 At least seven children have died in CBP custody since last year, including Carlos Gregorio Hernández Vásquez, a Guatemalan teenager who died after being diagnosed with influenza. Jim Daley, Scientific American, "Detained Migrant Children Need Continuous Medical Care," 26 July 2019 Swine influenza is a respiratory disease in pigs that’s caused by type A influenza viruses. USA TODAY, "Penal farm to produce farm, music under the sea: News from around our 50 states," 16 July 2019 For instance, one 2015 study showed that having one or two copies of CCR5-∆32 nearly quadrupled a person's odds of dying from influenza. Michael Greshko, National Geographic, "First gene-edited babies may be at risk of early death," 3 June 2019 In addition to the canine influenza vaccine, a variety of vaccinations will be offered for dogs and cats, including rabies, Bordetella, Leptospirosis, Panleukopenia, and other core vaccines and heart worm treatments. Joan Morris, The Mercury News, "Horrifying San Francisco dog-on-dog attack on a crowded street," 3 July 2019

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

1743, in the meaning defined at sense 1a

History and Etymology for influenza

Italian, literally, influence, from Medieval Latin influentia; from the belief that epidemics were due to the influence of the stars

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Dictionary Entries near influenza

influencive

influent

influential

influenza

influx

influxion

info

Statistics for influenza

Last Updated

25 Aug 2019

Look-up Popularity

Time Traveler for influenza

The first known use of influenza was in 1743

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More Definitions for influenza

influenza

noun

English Language Learners Definition of influenza

medical : a common illness that is caused by a virus and that causes fever, weakness, severe aches and pains, and breathing problems

influenza

noun
in·​flu·​en·​za | \ ˌin-flü-ˈen-zə How to pronounce influenza (audio) \

Kids Definition of influenza

: a very contagious virus disease like a severe cold with fever

influenza

noun
in·​flu·​en·​za | \ ˌin-(ˌ)flü-ˈen-zə How to pronounce influenza (audio) \

Medical Definition of influenza

1a : an acute, highly contagious, respiratory disease caused by any of three orthomyxoviruses:
(1) or influenza A : moderate to severe influenza that in humans is marked especially by sudden onset, fever, sore throat, fatigue, muscle aches, inflammation of the respiratory mucous membranes, and cough, is caused by any of several subtypes (such as H1N1, H2N2, or H3N2) of an orthomyxovirus (species Influenza A virus of the genus Influenzavirus A) infecting humans and various animals (such as birds or pigs), and may occur in seasonal epidemics or sometimes pandemics following mutation of the causative virus — see asian flu, avian influenza, bird flu, hong kong flu, spanish flu, swine flu, swine influenza
(2) or influenza B : influenza with less severe symptoms that is caused by an orthomyxovirus (species Influenza B virus of the genus Influenzavirus B) infecting only humans and especially children and that may occur in seasonal epidemics but not pandemics
(3) or influenza C : mild influenza that is often asymptomatic, is caused by an orthomyxovirus (species Influenza C virus of the genus Influenzavirus C) infecting only humans, and does not occur in epidemics or pandemics
b : any human respiratory infection of undetermined cause not used technically
2 : any of various viral diseases of domestic animals (as shipping fever of horses) marked especially by fever, respiratory symptoms, and inflammation of mucous membranes

Note: All types of influenza are commonly called "the flu."

Other Words from influenza

influenzal \ -​zəl How to pronounce influenzal (audio) \ adjective
influenzal pneumonia influenzal symptoms

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More from Merriam-Webster on influenza

Spanish Central: Translation of influenza

Nglish: Translation of influenza for Spanish Speakers

Britannica English: Translation of influenza for Arabic Speakers

Britannica.com: Encyclopedia article about influenza

Comments on influenza

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