A dynasty (UK: i/, US: i/) is a sequence of rulers from the same family, usually in the context of a feudal or monarchical system, but sometimes also appearing in electiverepublics. Alternative terms for "dynasty" may include "house", "family" and "clan", among others. The longest-surviving dynasty in the world is the Imperial House of Japan, otherwise known as the Yamato dynasty, whose reign is traditionally dated to 660 BC.
The word "dynasty" is sometimes used informally for people who are not rulers but are, for example, members of a family with influence and power in other areas, such as a series of successive owners of a major company. It is also extended to unrelated people, such as major poets of the same school or various rosters of a single sports team.
The word "dynasty" derives from Latindynastia, which comes from Greekdynastéia (δυναστεία), where it referred to "power", "dominion", and "rule" itself. It was the abstract noun of dynástēs (δυνάστης), the agent noun of dynamis (δύναμις), "power" or "ability", from dýnamai (δύναμαι), "to be able".