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

Moderna's combo flu and COVID vaccine provided a strong immune response in older adults, with levels comparable to getting the flu and COVID shots separately, according to the company's results from a late-stage clinical trial. —Youri Benadjaoud, ABC News, 10 June 2024

Those approvals for other test products for flu, RSV and other diseases didn’t pan out. —Natallie Rocha, San Diego Union-Tribune, 7 June 2024

Moreover, mink can be infected by avian and human flu viruses simultaneously, which could allow the viruses to swap genes and for the resulting pathogen to become more adept at spreading among people. —Andrew Joseph, STAT, 5 June 2024

Bird flu detected in San Francisco wastewater and chickens. —Ryan Fonseca, Los Angeles Times, 5 June 2024

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

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