Overview
A clan is a group of people united by actual or perceived kinship
and descent. Even if lineage details are unknown, clans may claim descent from founding member or apical ancestor. Clans, in indigenous societies, were not endogamous, meaning that their members can not marry one another. Clans preceded more centralized forms of community organization and government, and exist in every country. Members may identify with a coat of arms or other symbol. Kinship-based groups may also have a symbolic ancestor, whereby the clan shares a "stipulated" common ancestor who serves as a symbol of the clan's unity.
Etymology
The English word "clan" is derived from old Irish meaning "children", "offspring", "progeny" or "descendants"; it is not from the word for "family" or "clan" in either Irish or Scottish Gaelic. According to the Oxford English Dictionary, the word "clan" was introduced into English in around 1425, as a descriptive label for the organization of society in Ireland and the Scottish Highlands.
None of the Irish and Scottish Gaelic terms for kinship groups is cognate to English clan; Scottish Gaelic means "descendants":
means (English) "clan"
means "family" in the sense of the nuclear family, or can include more distant relatives living in the same house
means either "family" in the sense of "household", or everyone who lives in the house, including non-relatives
means "family" in the broad sense of "kinsfolk"
Clans as political units
In different cultures and situations, a clan usually has different meaning than other kin-based groups, such as tribes and bands. Often, the distinguishing factor is that a clan is a smaller, integral part of a larger society such as a tribe, chiefdom, or a state. In some societies, clans may have an official leader such as a chief, matriarch or patriarch; or such leadership role is performed by elders. In others, leadership positions may have to be achieved.
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