The Three Martyrs: St Sebastian, St Boniface and St Thomas of Canterbury Catholic Church

Useful Definitions of the Structures in the Catholic Church

What is a Catholic Bishops' Conference?

An episcopal conference, sometimes called a conference of bishops, is an official assembly of the bishops of the Catholic Church in a given territory. ... Individual bishops do not relinquish their immediate authority for the governance of their respective dioceses to the conference (Wikipedia).

What is an Archdiocese?

Dioceses ruled by an archbishop are commonly referred to as archdioceses; most are metropolitan sees, being placed at the head of an ecclesiastical province. A few are suffragans of a metropolitan see or are directly subject to the Holy See.

The term 'archdiocese' is not found in Canon Law, with the terms "diocese" and "episcopal see" being applicable to the area under the ecclesiastical jurisdiction of any bishop.[8] If the title of archbishop is granted on personal grounds to a diocesan bishop, his diocese does not thereby become an archdiocese (Wikipedia).

What is a Diocese?

The group of churches that a bishop supervises is known as a diocese. Typically, a diocese is divided into parishes that are each overseen by a priest.

The original dioceses, in ancient Rome, were political rather than religious. Rome was divided into dioceses, each of which was made up of many provinces. After Christianity became the Roman Empire's official religion in the 4th century, the term gradually came to refer to religious districts. The Catholic Church has almost 3,000 dioceses. The Greek root of diocese is dioikesis, "government, administration, or province." (Vocabulary.com).

As of April 2020, in the Catholic Church there are 2,898 regular dioceses: 1 papal see, 649 archdioceses (including 9 patriarchates, 4 major archdioceses, 560 metropolitan archdioceses, 76 single archdioceses) (Wikipedia).

What is the difference between a Diocese and an Archdiocese?

Each diocese is within a Province - a group of Dioceses - the Archdiocese is the main Diocese within that Diocese. The bishop of that Archdiocese is therefore automatically an Archbishop. If a bishop has been made an Archbishop personally is referred to as an Archbishop but it does not make their Diocese an Archdiocese.

What is a Deanery?

A subdivision of a diocese, consisting of a number parishes, over which presides a dean appointed by a bishop. The duty of the dean is to watch over the clergy of the deanery, to see that they fulfill the orders of the bishop, and observe the liturgical and canon laws. He summons the conference of the deanery and presides at it. Periodically he makes a report to the bishop on conditions in the deanery.www.catholicculture.org

What is a Parish?

In the Roman Catholic Church, a parish (Latin: parochia) is a stable community of the faithful within a particular church, whose pastoral care has been entrusted to a parish priest (Latin: parochus), under the authority of the diocesan bishop. It is the lowest ecclesiastical subdivision in the Catholic episcopal polity, and the primary constituent unit of a diocese. In the 1983 Code of Canon Law, parishes are constituted under cc. 515–552, entitled "Parishes, Pastors, and Parochial Vicars." Wikipedia