A Dictionary of Music and Musicians/Cantoris
CANTORIS. One of the most prominent features of the singing in the services of the Christian churches is its antiphonal character; that is, the manner in which the singers on either side of the church answer one another in the chants or in passages of the music. In order to distinguish the sides from one another in English cathedrals the words Decani and Cantoris are used, the former being the side of the dean's stall on the south or right-hand side when facing the altar, and the latter that of the cantor or precentor on the north or left-hand side.
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