mentioner vs utterer

mentioner and utterer both are nouns.

Word	Noun	Adjective	Verb	Adverb
mentioner	Yes	No	No	No
utterer	Yes	No	No	No

As nouns, utterer is a hypernym of mentioner; that is, utterer is a word with a broader meaning than mentioner:

mentioner: a speaker who refers to something briefly or incidentally
utterer: someone who expresses in language; someone who talks (especially someone who delivers a public speech or someone especially garrulous)

Other hypernyms of mentioner include speaker, talker, verbaliser, verbalizer.

mentioner (noun)	utterer (noun)
a speaker who refers to something briefly or incidentally	someone who expresses in language; someone who talks (especially someone who delivers a public speech or someone especially garrulous)
	someone who circulates forged banknotes or counterfeit coins
	an organism that can utter vocal sounds