cytomegalovirus cy·to·meg·a·lo·vi·rus (sī'tə-měg'ə-lō-vī'rəs)
n.
Abbr. CMV Any of a group of herpes viruses that attack and enlarge epithelial cells. Such viruses also cause a disease of infants characterized by circulatory dysfunction and microcephaly. Also called visceral disease virus.