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Medical Term:


Pronunciation: nū′mō-vī′rŭs

Definition: A genus of viruses (family Paramyxoviridae) including respiratory syncytial virus, which causes severe lower respiratory tract disease in infants. Nucleocapsids are 13–15 nm in diameter and thus intermediate in size between other Paramyxoviridae and the Orthomyxoviridae; cytoplasmic inclusions are considerably more dense than those of other viruses in the family.