cantata vs classical music

cantata and classical music both are nouns.

Word	Noun	Adjective	Verb	Adverb
cantata	Yes	No	No	No
classical music	Yes	No	No	No

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

cantata: a musical composition for voices and orchestra based on a religious text
classical music: traditional genre of music conforming to an established form and appealing to critical interest and developed musical taste

Other hypernyms of cantata include classical, serious music.

cantata (noun)	classical music (noun)
a musical composition for voices and orchestra based on a religious text	traditional genre of music conforming to an established form and appealing to critical interest and developed musical taste