refrain vs vocal

refrain and vocal both are nouns.

Word	Noun	Adjective	Verb	Adverb
refrain	Yes	No	Yes	No
vocal	Yes	Yes	No	No

refrain (noun)	vocal (noun)
the part of a song where a soloist is joined by a group of singers	music intended to be performed by one or more singers, usually with instrumental accompaniment
	a short musical composition with words

refrain (adjective)	vocal (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

refrain (verb)	vocal (verb)
choose not to consume
resist doing something