Paramyxoviridae
noun plural
Para·myxo·vi·ri·dae
| \ ˌpar-ə-ˌmik-sə-ˈvir-ə-ˌdē
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Medical Definition of Paramyxoviridae
: a family of large single-stranded RNA viruses that have a helical nucleocapsid and lipid-containing envelope and that include the parainfluenza viruses, respiratory syncytial virus, and the causative agents of canine distemper, measles, mumps, Newcastle disease, and rinderpest — see morbillivirus, rubulavirus