Clan (noun)

1. A group of families or households, especially among Scottish Highlanders, descended from a common ancestor and having a common surname.
2. A group of people united by a common interest or common characteristics.
3. A group of people or animals that are closely related.

Origin:

Late 16th century (as a scottish word in the sense "children of a common ancestor"): from scottish gaelic clann "offspring," of unknown origin.

Examples:

1. He was the chief of the clan.
2. The clan was very powerful in the region.
3. The clan was made up of several families with the same last name.
4. The clan of lions was led by a powerful male lion.
5. A clan of programmers who work on open source software.