Chieftain
A chieftain or chief was the leader of a tribal society. The Capellan title of "High Teer" was comparable in use to the title of "high chief". (TOS: "Friday's Child")
In 1996, Porter patronizingly called Chakotay chief. (VOY: "Future's End, Part II")
In 2268, the Yang Cloud William was a chief, as had been his father. Only Omega IV's chiefs and their sons were permitted to read the "E Pleb Neesta". James T. Kirk later pointed out that the document was not just meant for chiefs, but all people (TOS: "The Omega Glory")
Also that year, Goro was the chief of an American Indian tribe on Amerind. (TOS: "The Paradise Syndrome")
In 2319, the Mordanite Karnas' father was a ruling chief of a tribal family unit on Mordan IV until he was assassinated by order of Peretor Sain. (TNG: "Too Short A Season")
In 2344, Chakotay and his father Kolopak met a Earth Sky Spirit chief while searching for their ancestors. (VOY: "Tattoo")