noun
influential family; powerful house
Historical term for a family or clan with significant political or social power, often used in pre-modern contexts. The gloss 'the man in power' reflects a possible metonymic extension, but the core meaning is the family itself.
平安時代には、勢家が政治を動かしていた。
During the Heian period, influential families controlled politics.
この地域の勢家は代々、土地を所有してきた。
The powerful family of this region has owned the land for generations.