, or the , is a major metropolitan area in Japan that is centered on the city of Nagoya (the "Chà «kyà Â", i.e., the "capital in the middle") in Aichi Prefecture. The area makes up the most urbanized part of the Tà Âkai region. The population is 9,439,000 in 3,704 square kilometers of built-up land area. Nevertheless, like most of Japan's major metro areas, the core of it lies on a fertile alluvial plain, in this case, the Nà Âbi Plain.
It is among the 50 most populous metropolitan areas in the world, and is the third most populous metropolitan area in Japan (after Greater Tokyo and Osaka-Kobe-Kyoto), containing roughly 7% of Japan's population. Historically, this region has taken a back seat to the other two power centers, both politically and economically; however, the agglomeration of Nagoya is the world's 22nd-largest metro area economy, in terms of gross metropolitan product at purchasing power parity in 2014, according to a study by the Brookings Institution. The GDP of Greater Nagoya, Nagoya Metropolitan Employment Area, was US$256.3 billion in 2010.
The metropolitan area stretches beyond the central city of Nagoya to other municipalities in Aichi Prefecture, as well as neighboring Gifu and Mie prefectures.
There are at least 38 passenger train lines in the Greater Nagoya area. JR runs six, Nagoya Subway seven, Meitetsu 18, Kintetsu four, and five other operators one each.
Per Japanese census data, and , Chà «kyà  metropolitan area, also known as greater Nagoya, has had continuous population growth.
The area defined by the Chukyo Area Person-Trip Survey, a study of commuter movement, is slightly different from the census definition. It includes southern Aichi and areas immediately north of Gifu City. It adds two cities in Aichi Prefecture (Tahara and Toyohashi) and two cities in Gifu Prefecture (Mino and Seki). Additionally, it excludes two cities in Gifu Prefecture (Ena and Nakatsugawa).