church music vs musical genre

church music and musical genre both are nouns.

Word	Noun	Adjective	Verb	Adverb
church music	Yes	No	No	No
musical genre	Yes	No	No	No

As nouns, musical genre is a hypernym of church music; that is, musical genre is a word with a broader meaning than church music:

church music: genre of music composed for performance as part of religious ceremonies
musical genre: an expressive style of music

Other hypernyms of church music include music genre, musical style.

church music (noun)	musical genre (noun)
genre of music composed for performance as part of religious ceremonies	an expressive style of music