Influenza (coll.) (3)
I believe the answer is:
flu
(Other definitions for flu that I've seen before include "Winter ailment" , "In brief, winter illness" , "Influenza, in short" , "Viral infection (colloq.)" , "Swine --; gastric --" .)
I believe the answer is:
flu
(Other definitions for flu that I've seen before include "Winter ailment" , "In brief, winter illness" , "Influenza, in short" , "Viral infection (colloq.)" , "Swine --; gastric --" .)