mentioner vs speaker

mentioner and speaker both are nouns.

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

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

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

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

mentioner (noun)	speaker (noun)
a speaker who refers to something briefly or incidentally	electro-acoustic transducer that converts electrical signals into sounds loud enough to be heard at a distance
	someone who expresses in language; someone who talks (especially someone who delivers a public speech or someone especially garrulous)