influenza
in.flu.en.za \.in-(.)flu:-'en-z*\ n [It, lit., influence, fr. ML influentia; fr. the belief that epidemics we]re due to the influence of the stars 1: an acute highly contagious virus disease characterized by sudden onset, fever, prostration, severe aches and pains, and progressive inflammation of the respiratory mucous membrane; broadly : a human respiratory infection of undetermined cause 2: any of numerous febrile usu. virus diseases of domestic animals marked b y respiratory symptoms, inflammation of mucous membranes, and often systemic involvement
Webster's English Dictionary