IPA: /ˈproʊvaɪrəs/
KK: /ˈproʊvaɪrəs/
A type of virus that becomes part of the genetic material of a host cell and can be copied along with it without destroying the cell.
The provirus can remain dormant in the host's DNA for many years before becoming active.
Provirus is formed from "pro-" (meaning before) and "virus" (from Latin, meaning poison or slimy liquid). The term refers to a virus that integrates into the host's genome before it becomes active, hence the prefix indicating its prior state.
Think of 'before' ('pro-') a virus becomes active — that's why provirus refers to a virus that is in a dormant state before it starts to affect the host.