poglavar

1. (of a church, state) head; leader
   Patrijarh je poglavar Srpske pravoslavne crkve. — The Patriarch is the head of the Serbian Orthodox Church.
   Sastali su se poglavari dve države. — The heads of the two states met.
2. (of a tribe, clan) chieftain; chief
   Poglavar plemena je doneo konačnu odluku. — The tribal chief made the final decision.

Usually followed by a genitive: poglavar crkve, poglavar države.