monophonic music vs monophony

monophonic music and monophony both are nouns.

Word	Noun	Adjective	Verb	Adverb
monophonic music	Yes	No	No	No
monophony	Yes	No	No	No

As nouns, monophonic music and monophony are synonyms defined as:

monophonic music and monophony: music consisting of a single vocal part (usually with accompaniment)

Other synonyms of monophonic music include monody.

monophonic music (noun)	monophony (noun)
music consisting of a single vocal part (usually with accompaniment)	music consisting of a single vocal part (usually with accompaniment)