Wikipedia
A regiopolis is a city outside the core of a metropolitan area, that serves as an independent driving force for development within a larger region. The concept is used to develop midsized urban regions within regional, national and global contexts. For its surrounding region, the terms regiopolis region and regiopolitan area can be used and may be shortened to regio (similar to metropolitan area and metro).
The term regiopolis is a hybrid combination of the words region and polis ( Greek: "city"), and is used in the context of urban and regional planning. It was developed by professors Iris Reuther and Jürgen Aring in Germany in 2006, with Rostock as the first model regiopolis. To use and further develop their common potential, various cooperations between the regiopolis, its surrounding region, business partners and the closest metropolitan areas are fostered.