vocaliser vs vocalizer

vocaliser and vocalizer both are nouns.

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

As nouns, vocaliser and vocalizer are synonyms defined as:

Other synonyms of vocaliser include singer, vocalist.

As nouns, vocaliser and vocalizer are synonyms defined as:

Other synonyms of vocaliser include utterer.

vocaliser (noun)	vocalizer (noun)
a person who sings	a person who sings
an organism that can utter vocal sounds	an organism that can utter vocal sounds