cytomegalovirus cy·to·meg·a·lo·vi·rus (sī'tə-měg'ə-lō-vī'rəs)
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.
Any of a group of herpes viruses of the genus Cytomegalovirus that cause enlargement and abnormal structures in the cell nucleus (known as nuclear inclusions) in infected cells. Although the virus usually causes minor or no symptoms in normal adults, it is a common cause of opportunistic infections in immunosuppressed patients and can cause life-threatening congenital infections.