Definition of influenza virus in US English:

influenza virus

noun

  • The causative agent of influenza; (in later use) specifically any orthomyxovirus of the genera Influenzavirus A, Influenzavirus B, and Influenzavirus C.

Origin

Late 19th century. From influenza + virus.

Pronunciation

influenza virus

/ˌɪnflʊˈɛnzə ˈvʌɪrəs/