ethnic music vs popular music

ethnic music and popular music both are nouns.

Word	Noun	Adjective	Verb	Adverb
ethnic music	Yes	No	No	No
popular music	Yes	No	No	No

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

ethnic music: the traditional and typically anonymous music that is an expression of the life of people in a community
popular music: any genre of music having wide appeal (but usually only for a short time)

Other hypernyms of ethnic music include popular music genre.

ethnic music (noun)	popular music (noun)
the traditional and typically anonymous music that is an expression of the life of people in a community	any genre of music having wide appeal (but usually only for a short time)