noun.
A district or division of a country; a province: now obsolete except when used with reference to Norway, an episcopal diocese (stift) of which, as a geographical division of the country, is sometimes regarded as a province, though it has no provincial civil administration.
noun.
Under the Roman empire after Diocletian and Constantine, a subdivision of a prefecture, comprising a number of provinces; hence, a corresponding extent of territory as an ecclesiastical division, including a number of provinces or eparchies, each province again containing a number of parœciæ, which themselves finally came to be called dioceses in the following (modern) sense.
noun.
The district, with its population, falling under the pastoral care of a bishop.