Abun (in Europe erroneously known as Abuna, which is the status constructus form used when a name follows: Ge'ez አቡነ ’abuna/abune, 'our father'; Amharic and Tigrinya) is the honorific title used for any bishop of the Ethiopian Orthodox Tewahedo Church as well as of the Eritrean Orthodox Tewahedo Church. It was historically used solely for the head of the Coptic Orthodox Church in Ethiopia during the more than 1000 years when the Coptic Patriarchate of Alexandria appointed only one bishop at a time to serve its Ethiopian flock. When referred to without a name following, it is Abun, and if a name follows, it becomes Abuna ... (e.g., Abuna Paulos).
Abunã is a municipality in the Rondônia state of Brazil. It is situated in the Amazon Basin on the right bank of the Madeira River upstream from its confluence with the Abuna River. The Abuna River and the Madeira River upstream from their confluence mark the boundary between Brazil and Bolivia, and so Abunã is across the river from the Bolivia.