A metropolis (in Greek metera = mother and polis = city/town) is a major City, which is an economical and cultural center for some Country, and usually a hub for its international connections.
The word comes from the Greek metropolis ("mother city") (pl. metropoleis) which is how the Greek colonies of antiquity referred to their original cities, with whom they retained cultic and political-cultural connections. The word was used in post-classical Latin for the chief city of a province, the seat of the government, and in particular ecclesiastically for the seat or see of a Metropolitan bishop to whom suffragan bishops were responsible. This usage equates the province with the Diocese or see.
In modern usage the word is used for a Metropolitan area, a set of adjacent and interconnected cities clustered around a major urban center. In this sense "metropolitan" usually means "spanning the whole metropolis" (as in "metropolitan administration"); or "proper of a metropolis" (as in "metropolitan life", and opposed to "provincial" or "rural").
In French the Cognate word métropole designates the part of a country near or on the European continent; in the case of France, this would mean France without its overseas departments.