Wiktionary
prophage
n. (context biology English) The latent form of a bacteriophage in which the viral genome is inserted into the host chromosome.
Wikipedia
Prophage
A prophage is a bacteriophage (often shortened to "phage") genome inserted and integrated into the circular bacterial DNA chromosome or existing as an extrachromosomal plasmid. This is a latent form of a phage, in which the viral genes are present in the bacterium without causing disruption of the bacterial cell.
Usage examples of "prophage".
During this stage, the host bacterium reproduces the prophage or integrated phage genome with its own.