Choir
(I) A company of church singers. (2) The part of the church appropriated to the singers. In English churches (Anglican) the choir is divided into two parts, called the decani, or choir on the dean's side, and cantori, or choir on the cantor's side.
When chanting, they generally sing antiphonally, joining in the "gloria." In anthems the words decani and cantoris are printed to indicate which side is to sing a given part. on