A metropolis () is a large city or conurbation which is a significant economic, political, and cultural center for a country or region , and an important hub for regional or international connections, commerce, and communications. The term is AncientGreek (μητρόπολις) and means the " mother city " of a colony (in the ancient sense), that is, the city which sent out settlers. This was later generalized to a city regarded as a center of a specified activity, or any large, important city in a nation.
A big city belonging to a larger urban agglomeration, but which is not the core of that agglomeration, is not generally considered a metropolis but a part of it. The plural of the word is metropolises, although the Latin plural is metropoles, from the Greek metropoleis (μητρoπόλεις).
For urban centers outside metropolitan areas that generate a similar attraction at smaller scale for their region , the concept of the regiopolis ("regio" for short) was introduced by German academics in 2006.