"Decanatus" is a word in LAW AND LEGAL

In ecclesiastical law. In its technical sense, this term includes ec-clesiastical preferments to which rank or public office is attached, …

of Deanery

The residence of a dean.

The office or the revenue of a dean. See the Note under Benefice, n., 3.

The territorial jurisdiction of a dean.

Pertaining to a dean or deanery.

The circuit of an archdeacon’s and rural dean's Jurisdictions. Every rural deanery is divided into parishes. See 1 Steph. Comm. …

In English ecclesias-tical la... Very ancient officers of the church, almost grown out of use, until about the middle of …