flu

noun

ˈflü 

1

: influenza

2

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

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

Egg prices have surged to record levels following supply chain disruptions and avian flu outbreaks, reaching an average of $6.23 per dozen in March, according to the Bureau for Labor Statistics. —Matt Robison, MSNBC Newsweek, 16 Apr. 2025

As such, seasonal flu vaccines are not designed to protect against avian influenza. —Hanna D. Paton, The Conversation, 15 Apr. 2025

There is an immediate need for all blood types, especially type O. Donors must be at least 17 years old and should be in good health with no cold, flu, or COVID-19 symptoms. —Anne Gelhaus, Mercury News, 14 Apr. 2025

Keto diets have also shown the potential to enhance chemotherapy; improve memory; and even fight the flu in mouse models. —Michael Franco, New Atlas, 13 Apr. 2025

Word History

Etymology

by shortening

First Known Use

1839, in the meaning defined at sense 1

Phrases Containing flu

• anti-flu
• Asian flu
• bird flu
• blue flu
• flu season
• swine flu
• yuppie flu

Rhymes for flu

• blew
• blue
• boo
• brew
• chew
• chou
• clue
• coo
• coup
• crew
• cue
• dew

Kids Definition

flu

noun

ˈflü 

1

: influenza sense 1

2

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

flu-like

ˈflü-ˌlīk

adjective

Medical Definition

flu

noun

ˈflü 

1

: influenza

2

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

flu-like

-ˌlīk 

adjective

also flulike

flu-like symptoms