chorister vs vocaliser

chorister and vocaliser both are nouns.

Word	Noun	Adjective	Verb	Adverb
chorister	Yes	No	No	No
vocaliser	Yes	No	No	No

As nouns, vocaliser is a hypernym of chorister; that is, vocaliser is a word with a broader meaning than chorister:

Other hypernyms of chorister include singer, vocalist, vocalizer.

chorister (noun)	vocaliser (noun)
a singer in a choir	a person who sings
	an organism that can utter vocal sounds