Find the word definition

Wikipedia
Megaviridae

The Megaviridae are a proposed family of double-stranded DNA viruses that have not been recognized by the ICTV. The members of this proposed family are the DNA viruses with the largest known genomes. The classification of this group is ongoing but its members include Megavirus, Mimivirus, Phaeocystis globosa virus and Cafeteria roenbergensis virus.