clan

A clan is a group of people united by actual or perceived kinship
and descent. Even if lineage details are unknown, a clan may claim descent from a founding member or apical ancestor who serves as a symbol of the clan's unity. Many societies' exogamy rules are on a clan basis, where all members of one's own clan, or the clans of both parents or even grandparents, are excluded from marriage as incest.
Clans preceded more centralized forms of community organization and government, and have existed in every country. Members may identify with a coat of arms or other symbol.