Chancel

[2] This is one definition, sometimes called the "strict" one; in practice in churches where the eastern end contains other elements such as an ambulatory and side chapels, these are also often counted as part of the chancel, especially when discussing architecture.

[3] In smaller churches, where the altar is backed by the outside east wall and there is no distinct choir, the chancel and sanctuary may be the same area.

In a cathedral or other large church, there may be a distinct choir area at the start of the chancel (looking from the nave), before reaching the sanctuary, and an ambulatory may run beside and behind it.

As well as the altar, the sanctuary may house a credence table and seats for officiating and assisting ministers.

In the West the ciborium, an open-walled but usually roofed structure sheltering the altar, became common, and was originally fitted with curtains that were drawn and pulled back at different points in the Mass, in a way that some Oriental Orthodox churches still practice today.

In many orders "choir monk" was a term used to distinguish the educated monks who had taken full vows, or were training to do so, from another class, called "lay brothers" or other terms, who had taken lesser vows and mostly did manual tasks, including farming the monastery's land.

After the Reformation Protestant churches generally moved the altar (now often called the communion table) forward, typically to the front of the chancel, and often used lay choirs who were placed in a gallery at the west end.

With the emphasis on sermons, and their audibility, some churches simply converted their chancels to seat part of the congregation.