1. the capital city (often Tokyo) area (typically within 50 km of city's centre) (center)
Wikipedia definition
2. Capital regionA capital region, also called a national capital region, capital district or capital territory is a common term for the region or district surrounding the capital city of a country or any other administrative division. It is not always the official term for the region, but may sometimes be used as an informal synonym. Country-level examples include: The term is also used by some subnational entities as follows:
Read “Capital region” on English Wikipedia
Read “首都圏” on Japanese Wikipedia
Read “Capital region” on DBpedia


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