polyphonic

Polyphonic, from Greek poly- 'many' and phone 'sound', describes a musical texture in which two or more independent melodic lines are performed simultaneously. Each line has its own contour and rhythm, and the lines interact to form harmony through counterpoint. This contrasts with monophony, a single melodic line, and with homophony, where a primary melody is supported by accompaniment.

The tradition began in medieval Europe with organum, where voices moved in parallel or with contrary motion to a chant. By the Renaissance, composers such as Josquin des Prez and Palestrina developed more elaborate polyphony, using imitation and shared motifs. The Baroque period further explored contrapuntal forms such as the fugue, in which a subject enters in succession in different voices.

In common practice music, polyphony remained central in choral and instrumental works. Jazz and some folk musics also use polyphonic textures, through simultaneous, interwoven melodies. Polyphony is often contrasted with heterophony (variations of a single melody).

In modern usage, polyphony also describes the capability of instruments and software to produce multiple notes at once. Digital keyboards and synthesizers are rated by their maximum polyphony, and software implements voice allocation to manage several simultaneous lines.

Outside music, polyphony refers to multiple voices or viewpoints within a text or discourse, such as in certain literary theories that foreground diverse perspectives.