alliterator vs speaker

alliterator and speaker both are nouns.

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

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

alliterator: a speaker or writer who makes use of alliteration
speaker: someone who expresses in language; someone who talks (especially someone who delivers a public speech or someone especially garrulous)

Other hypernyms of alliterator include talker, utterer, verbaliser, verbalizer, author, writer.

alliterator (noun)	speaker (noun)
a speaker or writer who makes use of alliteration	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)