rhetorician vs public speaker

rhetorician and public speaker both are nouns.

Word	Noun	Adjective	Verb	Adverb
rhetorician	Yes	No	No	No
public speaker	Yes	No	No	No

As nouns, rhetorician and public speaker are synonyms defined as:

rhetorician and public speaker: a person who delivers a speech or oration

Other synonyms of rhetorician include orator, speechifier, speechmaker.

rhetorician (noun)	public speaker (noun)
a person who delivers a speech or oration	a person who delivers a speech or oration