Orthomyxoviridae
noun plural
Or·tho·myxo·vi·ri·dae
| \ ˌȯr-thō-ˌmik-sə-ˈvir-ə-ˌdē
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Medical Definition of Orthomyxoviridae
: a family of single-stranded RNA viruses that have a spherical or filamentous virion with numerous surface glycoprotein projections, a helical nucleocapsid, and a genome consisting of six to eight segments of RNA and that include the viruses causing influenza A, influenza B, and influenza C and a genus (Thogotovirus) of tick-borne viruses that occasionally infect humans