The word for it is diocese.
its jurisdiction
An archdiocese is the area under the jurisdiction of an archbishop. For example the Archdiocese of Boston is the city and surrounding area that is headed by the Archbishop of Boston. A smaller archdiocese is sometimes called an archbishopric. Likewise a diocese is the area under the jurisdiction of a bishop, and a patriarchate is the area under the jurisdiction of a patriarch, such as the Patriarch of Jerusalem, and so on.
General jurisdiction is 100% of the time. speical jurisdiction, normally has a time limit, area limit and controlled limitations.
Jurisdiction
In Christianity, a diocese is an administrative territorial unit administered by a bishop. It is also referred to as a bishopric or Episcopal Area (as in United Methodism) or episcopal see, though strictly the term episcopal see refers to the domain of ecclesiastical authority officially held by the bishop, and bishopric to the post of being bishop. The diocese is the key geographical unit of authority in the form of church governance known as episcopal polity. In the Roman Catholic Church and the Anglican Communion, an important diocese is called an archdiocese (usually due to size, historical significance, or both), which is governed by an archbishop, who may be exempt from or have metropolitan authority over the other ('suffragan') dioceses within a wider jurisdiction called an ecclesiastical province.
Jurisdiction is area overseen by an authority such as police.
territory
First, there are numerous churches called St John's Episcopal Church worldwide. Second, since the name is St John's Episcopal Church, then it means they are Episcopal. An Episcopal Church is not a Catholic Church.
Episcopal is spelled exactly as you have it spelled.
Jurisdiction can be defined as authority over a specific geographical area.
Some police do have jurisdiction on a dock. It technically depends on the specific area they are told to patrol. If the police officer is told to patrol the dock and it is in his jurisdiction, then he surely is in control of that area.
Jurisdiction is the area in which a person or institution has authority. It has particular reference to courts and legislatures, but can refer to any kind of official. Jurisdiction can be a geographical or conceptual area. E.g. "I'm sorry sir, I know you're a policeman in Texas, but you have no jurisdiction in Alberta, so hand over your gun." describes a geographical area. "Yes Mrs. Smith, I know you would like the Town Council to pass a by-law cutting off diplomatic relations with Russia, but Foreign Relations is not in the Council's jurisdiction." describes a conceptual jurisdiction.