\ ˈflü \

Definition of flu 

1 : influenza

2 : any of several virus diseases marked especially by respiratory or intestinal symptoms

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Other words from flu

flu-like \ˈflü-ˌlīk \ adjective

Examples of flu in a Sentence

He came down with a bad bout of the flu.

Recent Examples on the Web

The Massachusetts Medical Device Development Center, a collaboration involving the University of Massachusetts Lowell and Worcester campuses, has been chosen as one of eight business incubators to help eradicate the flu and sepsis. Morgan Hughes, BostonGlobe.com, "Curing the flu, wedding dresses for soldiers, and food for the elderly," 13 July 2018 In 2013, before the DBC prototype was operational, scientists from the lab worked with Chinese officials to manufacture a vaccine for an avian-flu strain. Laine Higgins, WSJ, "This Company Aims to Deliver DNA on Demand With Its Biological Fax Machine," 12 July 2018 But the concierge treatment has recently gained mainstream attention in larger cities, with hospital-unaffiliated IV hydration stations marketing themselves as one-stop cures for anything from flu symptoms to hangovers. Zahria Rogers, The Courier-Journal, "Concierge IV hydration therapy service seeks to rehydrate Louisville," 12 July 2018 Two of the Hello Girls died in France from the Spanish flu epidemic. Meg Jones, Milwaukee Journal Sentinel, "Wisconsin documentarian sparks effort to honor World War I female phone operators with Congressional Gold Medal," 10 July 2018 Because the initial symptoms could be attributed to the flu, or later on, mental health problems, anti-NDMA receptor encephalitis can be hard to pin down at first. refinery29.com, "What Condition Does Chloë Grace Moretz Have In Brain On Fire?," 22 June 2018 What’s more, canine flu viruses are becoming increasingly diverse. Brigit Katz, Smithsonian, "The Next Flu Pandemic Might Come from Dogs," 9 June 2018 Luz Barajas and Carlos Cholcio brought their children, Carlos and Menserrat into the clinic for their annual flu shot. Julie Mazziotta, PEOPLE.com, "What to Know About the New Shingles Vaccine — and Why You Should Get It ASAP if You're Over 50," 5 July 2018 ImagineMD charges patients $149 a month, which includes visits and some services such as stitches, EKGs, joint injections and flu shots. Lisa Schencker, chicagotribune.com, "More doctors embrace membership fees, shunning health insurance," 22 June 2018

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

1839, in the meaning defined at sense 1

History and Etymology for flu

by shortening

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Phrases Related to flu

flu season

Statistics for flu

Last Updated

1 Sep 2018

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Time Traveler for flu

The first known use of flu was in 1839

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More Definitions for flu



English Language Learners Definition of flu

: a common disease that is caused by a virus and that causes fever, weakness, body aches, and breathing problems


\ ˈflü \

Kids Definition of flu

1 : influenza

2 : any of several virus diseases something like a cold


\ ˈflü \

Medical Definition of flu 

1 : influenza

2 : any of several chiefly viral illnesses marked especially by respiratory or gastrointestinal symptoms — see intestinal flu

Other words from flu

flu-like \-ˌlīk \ also flulike adjective
flu-like symptoms

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Comments on flu

What made you want to look up flu? Please tell us where you read or heard it (including the quote, if possible).


alleviating pain or harshness

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