1
2
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Worthy of your time: The Ohio Department of Health's website has tips for preventing the flu and a list of vaccine locations. Troy Smith, Axios, 28 Jan. 2025 Caldwell gave birth to Conor Scott a week earlier while dealing with the flu. Doug Feinberg, Chicago Tribune, 27 Jan. 2025 Just like regular flu, there are several strains of the avian flu circulating, but the most common is the H5N1 strain. Stephen Underwood, Hartford Courant, 24 Jan. 2025 Poultry Cases Bird flu continues to spread among commercial and backyard poultry. Meghan Bartels, Scientific American, 23 Jan. 2025 See all Example Sentences for flu 

Word History

Etymology

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 31 Jan. 2025.

Kids Definition

flu

noun
1
2
: any of several virus diseases that are something like a cold
flu-like
ˈflü-ˌlīk
adjective

Medical Definition

flu

noun
1
2
: 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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