Way overdue to document this : naviguessing is the art of navigating when you don’t know where you are.  Or as I would have said : “If we are where I think I am, now go …” when acting a navigator on family trips as a kid.  Part of the art is looking for evidence that gives confidence to a guess, usually expressed as percentages off a waypoint.
I think having a gps has both decreased and increased the need for naviguessing : decreased it because more easily accessible – on your dashboard or in your pocket;  increased it because you need to think the mapping data is up to date – or you should : the map is not the territory!