General terms:
* Chief: This is a very common term, often used for leaders in many cultures.
* Leader: This is a general term, but can be used for tribal heads.
* Elder: In some tribes, the leader may be the oldest or wisest member of the tribe.
* King/Queen: This is more common for larger, more organized societies, but can also apply to some tribes.
Specific terms:
* Sachem: This term is used for tribal leaders in some Native American cultures.
* Imam: This term is used for the leader of a tribe in some Islamic cultures.
* Sultan: This is the title for a ruler in some Islamic cultures.
* Sheikh: This is the title for a leader in some Arab cultures.
* Khan: This term is used for a tribal leader in some Mongolian and Turkic cultures.
Other factors:
* Gender: Some tribes have female leaders, while others have male leaders.
* Hereditary vs. Elected: Some leaders are chosen through heredity, while others are elected.
* Specific Role: The leader may have specific duties, like military leadership, religious authority, or lawmaking.
It's important to remember that there is no single answer to this question, as the title of the head of a tribe is culturally specific.