: any of several virus diseases marked especially by respiratory or intestinal symptoms
flu-like adjective

Examples of flu in a Sentence

He came down with a bad bout of the flu.
Recent Examples on the Web Infections Viral infections such as the common cold and influenza (the flu) are common culprits of a dry throat. Laura Schober, Health, 3 July 2024 While the vaccine would target H5N1, the mRNA technology would allow manufacturers to pivot quickly if another new flu strain emerges. Rachel Roubein, Washington Post, 3 July 2024 In humans, symptoms can resemble a typical flu – fever, sore throat, muscle aches, nausea and congestion, among others – but can also progress into more serious respiratory symptoms. Chris Mueller, USA TODAY, 3 July 2024 Avian flu viruses have caused periodic outbreaks in humans, with a high mortality rate. Lauren J. Young, Scientific American, 2 July 2024 See all Example Sentences for flu 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'flu.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


by shortening

First Known Use

1839, in the meaning defined at sense 1

Time Traveler
The first known use of flu was in 1839

Dictionary Entries Near flu

Cite this Entry

“Flu.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flu. Accessed 15 Jul. 2024.

Kids Definition


: any of several virus diseases that are something like a cold

Medical Definition


: any of several chiefly viral illnesses marked especially by respiratory or gastrointestinal symptoms see intestinal flu
flu-like adjective
also flulike
flu-like symptoms

More from Merriam-Webster on flu

Last Updated: - Updated example sentences
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