A general term used for viruses isolated from prokaryotes including bacteria, blue-green algae (cyanobacteria) and mollicutes (phytoplasma and spiroplasma). The viruses from these different host groups are termed bacteriophages, cyanophages and mycoplasmaphages, respectively. Found on http://ppathw3.cals.cornell.edu/glossary/Defs_P.htm
Phage: Short for bacteriophage, a virus that lives within a bacteria. A virus for which the natural host is a bacterial cell. Bacteriophages have been very important and heuristic in bacterial and molecular genetics. Phages were studied by (among others) Alfred Hershey, Max Delbruck and Salvador Luria who discovered that viruses could exchange gene... Found on http://www.medterms.com/script/main/art.asp?articlekey=4855