antiphon

Greek antiphōnon meant "sounding against," from anti "against" and phōnē "sound, voice." The term described responsive singing. It named a musical structure before it became a liturgical item. The idea is call and answer.

The Greek word passed into Latin as antiphona. By the 4th century, Ambrose of Milan introduced antiphonal psalmody in the West, and Augustine of Hippo died in 430 after praising it. The term fixed a practice of alternating choirs. The form moved from Greek music to church Latin.

Old French gave antiphone, and English took antiphon by the 14th century. The spelling reflects the Greek root but the pronunciation is English. The word narrowed to a specific chant, often framing psalms. The alternation remains in the meaning.

Antiphon now names a short chant sung before or after a psalm or canticle. It still implies response, even when sung by one choir. The word's core is auditory. Voice answers voice.