A province, prefecture, or territory, under the jurisdiction of an eparch or governor; esp., in modern Greece, one of the larger subdivisions of a monarchy or province of the kingdom; in Russia, a diocese or archdiocese.

a geographical area under the jurisdiction of a bishop in an Orthodox church.

In the Eastern Catholic Churches, a particular church governed by a bishop; equivalent to the term "diocese" used in the Latin Church.

a province in ancient Greece

a diocese of the Eastern Orthodox Church

a diocese of the Eastern Christian Church)

Eparchy is an anglicized Greek word, authentically latinized as eparchia and loosely translating as 'rule over something', but has the following specific meanings, both in political history and in the hierarchy of eastern churches.