bacteriophage
Concise Oxford English Dictionary © 2008 Oxford University Press:
bacteriophage /bakˈtɪərɪə(ʊ)feɪdʒ, -fɑːʒ/
▶noun Biology a kind of virus which parasitizes a bacterium by infecting it and reproducing inside it.
'bacteriophage' also found in these Oxford entries:

