homophony vs part music

homophony and part music both are nouns.

Word	Noun	Adjective	Verb	Adverb
homophony	Yes	No	No	No
part music	Yes	No	No	No

As nouns, part music is a hypernym of homophony; that is, part music is a word with a broader meaning than homophony:

homophony: part music with one dominant voice (in a homophonic style)
part music: vocal music for several voices in independent parts (usually performed without accompaniment)

homophony (noun)	part music (noun)
part music with one dominant voice (in a homophonic style)	vocal music for several voices in independent parts (usually performed without accompaniment)
the same pronunciation for words of different origins