\ ˈflü How to pronounce flu (audio) \

Definition of flu

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

Keep scrolling for more

Other Words from flu

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

Examples of flu in a Sentence

He came down with a bad bout of the flu.

Recent Examples on the Web

Vitamin C Everyone touts vitamin C for its abilities to ward off colds and flu, but this potent antioxidant may also improve skin's texture and appearance. Amy Capetta, Woman's Day, "5 Anti-Aging Supplements That May Actually Work," 16 Oct. 2018 In addition, if your child has a cold or the flu, he or she should be treated promptly. Mary Caldwell, ajc, "Childhood asthma: What you need to know," 26 June 2018 Matt Szczur was finally able to hold down food on Tuesday after battling the flu for several days. Kevin Acee, sandiegouniontribune.com, "Padres reliever Craig Stammen rolling, very different from a year ago," 11 Apr. 2018 When the teams last played on Feb. 10 in Boston, Larrañaga was battling the flu and wound up sleeping in the locker room the entire game. Michelle Kaufman, miamiherald, "What you need to know heading into a pivotal UM-Boston College basketball game | Miami Herald," 23 Feb. 2018 Charles’ wife Camilla, who is recovering from flu, also missed church. Frank Augstein, The Seattle Times, "Queen Elizabeth II riffs on wisdom, family’s busy year," 26 Dec. 2018 And even if these off-target mutations aren’t harmful, research has shown that a mutation in the CCR5 gene can make people more susceptible to dying from the flu. Angela Chen, The Verge, "Flawed DNA editing of alleged ‘designer babies’ may have put their health at risk," 29 Nov. 2018 In the current influenza season, the CDC has recorded 183 children who died from flu. Cathleen O'grady, Ars Technica, "A look at the virus behind seven deaths at a New Jersey facility," 25 Oct. 2018 People at high risk for serious complications from the flu should avoid pigs and should not enter swine barns. Emma Kate Fittes, Indianapolis Star, "Indiana resident catches rare form of flu following exposure to pigs at a county fair," 1 July 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.

See More

First Known Use of flu

1839, in the meaning defined at sense 1

History and Etymology for flu

by shortening

Keep scrolling for more

Learn More about flu

Dictionary Entries near flu








Statistics for flu

Last Updated

9 Jun 2019

Look-up Popularity

Time Traveler for flu

The first known use of flu was in 1839

See more words from the same year

Keep scrolling for more

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 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-like (audio) \ also flulike adjective
flu-like symptoms

Keep scrolling for more

More from Merriam-Webster on flu

Rhyming Dictionary: Words that rhyme with flu

Spanish Central: Translation of flu

Nglish: Translation of flu for Spanish Speakers

Britannica English: Translation of flu for Arabic Speakers

Britannica.com: Encyclopedia article about flu

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).


behavior toward others

Get Word of the Day daily email!

Test Your Vocabulary

Words for Summer: A Quiz

  • a closeup of a sunflower
  • Which of the following words means “of or relating to summer”?
Spell It

Can you spell these 10 commonly misspelled words?

Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!