What does "polyphony" mean?

Polyphony: Plurality of sounds and articulations expressed by the same vocal sign.

Additional senses

  1. 2.(Mus.) Composition in mutually related, equally important parts which share the melody among them; contrapuntal composition; -- opposed to homophony, in which the melody is given to one part only, the others filling out the harmony. See Counterpoint.

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