五城（pentapolis）一词来源于希腊语词汇“penta”（五）和“polis”（城邦），是地理上或制度上的5座城市的组群。

A pentapolis, from the Greek words πέντε (pente), "five" and πόλις (polis), "city(-state)" is a geographic and/or institutional grouping of five cities. Cities in the ancient world probably formed such groups for political, commercial and military reasons, as happened later with the Cinque Ports in England.