Polyphony is a type of musical texture consisting of two or more simultaneous lines of independent melody, as opposed to a musical texture with just one voice, monophony, or a texture with one dominant melodic voice accompanied by chords, homophony.

What is the meaning of Polyphone?

: a symbol or sequence of symbols having more than one phonemic value (such as a in English)

What is Poly in music?

Since poly- means "many", polyphonic music has "many voices".