I don't remember the term being used on a "label". But it would refer to any primer that is used for surfacing I would think. What a company uses as a name or description cold be misleading.
There are many different "primer surfacers" that would do filling. Everything from the old lacquer that barely fills 120 grit scratches with a couple of coats to polyester primer that could literally bury a quarter taped to your fender!
Is there a particular need you are after?
