\ ˈflü How to pronounce flu (audio) \

Definition of flu

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

Other Words from flu

flu-like \ ˈflü-​ˌlīk How to pronounce flu (audio) \ adjective

Examples of flu in a Sentence

He came down with a bad bout of the flu.
Recent Examples on the Web The mass death from the flu pandemic of 1918 changed everything. Praduman Jain, Forbes, 15 Nov. 2021 During the 1918-'19 flu pandemic, articles suggested diners simply move to another table if the waiter was coughing or sneezing. Carol Deptolla, Milwaukee Journal Sentinel, 5 Nov. 2021 Spanning multiple timelines, the post-apocalyptic limited series follows the survivors of a fictional flu pandemic that has wiped out much of the population. Ally Mauch, PEOPLE.com, 2 Nov. 2021 Since then, the race has persisted through World Wars and even the 1918 Spanish flu pandemic. Jimmy Golen, The Christian Science Monitor, 12 Oct. 2021 Even at the height of the 1918 flu pandemic, New York City’s theatre district remained open. The New Yorker, 10 Oct. 2021 Last year, flu activity reached the lowest numbers since the CDC began recording in 1997. Hannah Yasharoff, USA TODAY, 3 Nov. 2021 Officials say another factor in the decision is the possibility of a winter surge in COVID-19 cases coupled with the potential for a simultaneous local flu epidemic. David Garrick, San Diego Union-Tribune, 2 Nov. 2021 One person panic-buys a half-dozen carts full of groceries and barricades their apartment, another person isn't quite sure what this new flu is. Seija Rankin, EW.com, 2 Nov. 2021

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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Last Updated

18 Nov 2021

Cite this Entry

“Flu.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flu. Accessed 29 Nov. 2021.

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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 : influenza


\ ˈflü How to pronounce flu (audio) \

Kids Definition of flu

1 : influenza
2 : any of several virus diseases something like a cold


\ ˈflü How to pronounce flu (audio) \

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 How to pronounce flu (audio) \ also flulike adjective
flu-like symptoms

More from Merriam-Webster on flu

Nglish: Translation of flu for Spanish Speakers

Britannica English: Translation of flu for Arabic Speakers

Britannica.com: Encyclopedia article about flu


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