vocal vs musical composition

vocal and musical composition both are nouns.

Word	Noun	Adjective	Verb	Adverb
vocal	Yes	Yes	No	No
musical composition	Yes	No	No	No

As nouns, musical composition is a hypernym of vocal; that is, musical composition is a word with a broader meaning than vocal:

Other hypernyms of vocal include composition, opus, piece, piece of music.

vocal (noun)	musical composition (noun)
music intended to be performed by one or more singers, usually with instrumental accompaniment	a musical work that has been created
a short musical composition with words

vocal (adjective)	musical composition (adjective)
having or using the power to produce speech or sound
relating to or designed for or using the singing voice
given to expressing yourself freely or insistently
full of the sound of voices