Question

A region distinguished by uniformity of one or more characteristics that can serve as the basis for an areal generalization and of contrast with adjacent areas.

Answer 1

I believe the answer is: Formal region

Each formal region would be differentiated by their own unique government structure that separate each region with the other. Each border on the sides of each region would consist of some sort of boundaries ( could be natural or human made) that accepted by all regions as a legal separation between their jurisdiction.