The flu is a disease that's easily spread between people. When you have body aches, a fever, and a sore throat, you probably have the flu.

The word flu is shorthand for "influenza," the official name of this infectious, viral illness. It's not unusual to get the flu, especially in the winter, and while it usually isn't serious, it can be deadly for some groups of people. Your chances of getting the flu are greatly reduced if you get a flu shot. The Italian root influenza means "influenza" or "epidemic," but also "visitation" or "influence of the stars."

Definitions of flu

n an acute febrile highly contagious viral disease

grippe, influenza
Asian influenza, Asiatic flu
influenza caused by the Asian virus that was first isolated in 1957
swine flu, swine influenza
an acute and highly contagious respiratory disease of swine caused by the orthomyxovirus thought to be the same virus that caused the 1918 influenza pandemic
Type of:
contagion, contagious disease
any disease easily transmitted by contact
respiratory disease, respiratory disorder, respiratory illness
a disease affecting the respiratory system

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