flu has definitions from the field of medicine
1
[ noun ] (medicine) an acute febrile highly contagious viral disease

Synonyms

grippe influenza

Used in print

(St. Louis Post-Dispatch,...)

Harvey_Haddix , set_back by the flu this season , will start against his former Cardinal mates , who might be playing without captain Kenny_Boyer in tonight 's game at Busch_Stadium .

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