A city proper is the area contained within city limits. A city proper is not limited to a city; it can describe the complete area of any locality that fits the definition. The United Nations defines the term as "the single political jurisdiction which contains the historical city centre."

A metropolis is a large city or urban area 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 Greek 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.