In accordance with canon law

Canon law

Canon law is the body of laws & regulations made or adopted by ecclesiastical authority, for the government of the Christian organization and its members. It is the internal ecclesiastical law governing the Catholic Church , the Eastern and Oriental Orthodox churches, and the Anglican Communion of...

, a cathedral chapter is a college

College (canon law)

A college, in the canon law of the Roman Catholic Church, is a collection of persons united together for a common object so as to form one body. The members are consequently said to be incorporated, or to form a corporation.-History:...

 of clerics (chapter

Chapter (religion)

Chapter designates certain corporate ecclesiastical bodies in the Roman Catholic, Anglican and Nordic Lutheran churches....

) formed to advise a bishop

Bishop

A bishop is an ordained or consecrated member of the Christian clergy who is generally entrusted with a position of authority and oversight. Within the Catholic Church, Eastern Orthodox, Oriental Orthodox Churches, in the Assyrian Church of the East, in the Independent Catholic Churches, and in the...

 and, in the case of a vacancy

Sede vacante

Sede vacante is an expression, used in the Canon Law of the Catholic Church, that refers to the vacancy of the episcopal see of a particular church...

 of the episcopal see

Episcopal See

An episcopal see is, in the original sense, the official seat of a bishop. This seat, which is also referred to as the bishop's cathedra, is placed in the bishop's principal church, which is therefore called the bishop's cathedral...

 in some countries, to govern the diocese

Diocese

A diocese is the district or see under the supervision of a bishop. It is divided into parishes.An archdiocese is more significant than a diocese. An archdiocese is presided over by an archbishop whose see may have or had importance due to size or historical significance...

 in his stead. These councils are made up of canons

Canon (priest)

A canon is a priest or minister who is a member of certain bodies of the Christian clergy subject to an ecclesiastical rule ....

 and dignitaries; in the Roman Catholic church

Roman Catholic Church

The Catholic Church, also known as the Roman Catholic Church, is the world's largest Christian church, with over a billion members. Led by the Pope, it defines its mission as spreading the gospel of Jesus Christ, administering the sacraments and exercising charity...

 their creation is the purview of the pope

Pope

The Pope is the Bishop of Rome, a position that makes him the leader of the worldwide Catholic Church . In the Catholic Church, the Pope is regarded as the successor of Saint Peter, the Apostle...

. They can be "numbered," in which case they are provided with a fixed prebend

Prebendary

A prebendary is a post connected to an Anglican or Catholic cathedral or collegiate church and is a type of canon. Prebendaries have a role in the administration of the cathedral...

, or "unnumbered," in which case the bishop indicates the number of canons according to the rents.

Originally, it referred to a section of a monastic rule that was read out daily during the assembly of a group of canons or other clergy attached to a cathedra

Cathedra

A cathedra or bishop's throne is the chair or throne of a bishop. It is a symbol of the bishop's teaching authority in the Catholic Church and the Orthodox Church, and has in some sense remained such in the Anglican Communion and in Lutheran churches...

l or collegiate church

Collegiate church

In Christianity, a collegiate church is a church where the daily office of worship is maintained by a college of canons; a non-monastic, or "secular" community of clergy, organised as a self-governing corporate body, which may be presided over by a dean or provost...

. Later it came to be applied to the group of clergy itself.