What does antiphony mean?
The definition of antiphony
An*tiph”o*ny, n.; pl. Antiphonies.
Etym: [See Antiphon.]

1 A musical response; also, antiphonal chanting or signing.
2 An anthem or psalm sung alternately by a choir or congregation divided into two parts. Also figuratively. O! never more for me shall winds intone, With all your tops, a vast antiphony. R. Browning.