Virtual earth (ground) or "mid-rail generator"
Yes.  I've used the term "virtual ground" for a node used as reference for signals and that was generated by making roughly a mid point between two supplies.  I think that's pretty common usage.

I also agree that "virtual ground" can be used to describe the negative input of a opamp in inverting amplifier configuration, but only when the positive input is tied to ground.

This is a loose enough term that it should be defined before use, unless it is clear from context.  Talking to someone about virtual ground without context or a definition is wrong.