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

The group of illnesses comes a day after 10 people were hospitalized and tested positive for influenza after arriving by plane in New York from Dubai. Fox News, "Passengers on 2 flights from Europe arrive sick in Philly," 6 Sep. 2018 Aquatic birds, including wild ducks and migrating shorebirds, are considered nature’s main reservoir for influenza. Washington Post, "Bird flu hot spot: Scientists track virus in huge migration," 28 June 2018 In 2015 Alere—now owned by Abbott—got a CLIA waiver for a test for influenza based on extracting genetic material from a nasopharyngeal swab (way, way up your nose). Adam Rogers, WIRED, "Theranos Didn't Nuke the Diagnostics Business," 15 Mar. 2018 In the study, 332 patients who tested positive for influenza had heart attacks during the five-year period, with the week after the flu’s onset being the riskiest. Kathryn W. Foster, miamiherald, "The flu and heart attack risks are connected: Get the vaccine, doctors say | Miami Herald," 25 Feb. 2018 Several factors made Mary-Jo a likely candidate for serious influenza. Julie Washington, cleveland.com, "2018 Flu update: Flu shot did not prevent woman's death," 15 Feb. 2018 Though typically smiling and active, Simpson’s little ones are two of the more than 60,000 people in the U.S. who have tested positive for influenza. Blake Bakkila, Health.com, "Jessica Simpson Shares a Sweet Photo of Her Kids Sick With the Flu," 2 Feb. 2018 Amanda Franks tested positive for influenza on January 14 after experiencing a fever. Jason Duaine Hahn, PEOPLE.com, "New Hampshire Mother of 4 Dies of Flu Complications After Deciding Not to Take Tamiflu," 31 Jan. 2018 In the meantime, Landers said people should continue to practice common-sense measures: washing their hands; using alcohol gel to reduce the spread of germs; cough etiquette; and remaining at home while ill with influenza like illnesses. The Washington Post, AL.com, "Black Lives Matter activist who tackled Confederate flag killed in New Orleans," 7 Feb. 2018

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

19 May 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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