A group of people living as a household, traditionally consisting of parents and their children, and also (chiefly in early use) any servants, boarders, etc.; any household consisting of people who have long-term commitments to each other and are (usually) raising children; such a group as a fundamental social unit or institution.——牛津当代大辞典

a group of people who are related to each other, especially a mother, a father, and their children.——朗文当代大辞典  @en