also: いっけ
family; household; whole family
Refers to a family or household as a unit, often with the sense of the whole family together or the people one supports at home.
My father supported the family for many years.
夏休みに一家で北海道へ旅行した。
During summer vacation, the whole family traveled to Hokkaido.
Used for an established personal style, artistic line, scholarly school, or recognized approach; especially common in expressions such as 一家を成す.
彼は若くして日本画の世界で一家を成した。
He established his own school in the world of Japanese painting while still young.
gang; yakuza family
Underworld or crime-related use for a gang organization, especially a yakuza group treated as a 'family.'
警察は暴力団の一家の事務所を捜索した。
The police searched the office of a yakuza family.
I hear the Tanaka family is moving next month.
The whole family traveled to Hokkaido together.
一家 focuses on a single household or family unit living together, while 一族 extends to the wider clan beyond one household.
one's whole family and followers
breakup of a family; dispersal of a family