Pertaining to an antiphon (responsive chant or song)

ETYM Late Lat. antiphona, from Greek. Related to Anthem.
A verse or song to be chanted or sung in response; SYN. antiphony.
Anthem sung as a response during church service.
A response said or sung as part of the liturgy; a psalm etc. sung alternately by two choirs.
Choral music in Greek or Roman liturgy involving the exchange of responses between solo voice and choir, or between choral groups, hence antiphony.

Of, relating to, or suggesting an antiphon or antiphony.

Pertaining to an antiphon (responsive chant or song)

Alternate (responsive) singing by a choir in two parts.
Music exploiting directional and canonic opposition of widely spaced choirs or groups of instruments to create perspectives in sound. It was developed in 17th-century Venice by Giovanni Gabrieli and in Germany by his pupil Heinrich Schütz and Roland de Lassus; an example is the double choir motet Alma Redemptoris Mater 1604. The practice was revived in the 20th century by Bartók, Stockhausen, and Berio.