To add to your confusion, some "polishes" are really just non-abrasive glazes. And some glazes like Clearkote Red Moose Glaze contain light abrasives, making them light polishes as well as glazes.
IMO, a polish is abrasive. It will remove oxidation, stains, scratches, etc... Polishes can leave fillers and/or oils behind as well.
A glaze is a product which fills in minor imperfections, and is nonabrasive.
Usually, polishes are for removing imperfections, while glazes are used for hiding them.