is a specific kind of: speaker, talker, utterer, verbaliser, verbalizer.

is a broader term that covers: cross-examiner, cross-questioner | examiner, quizzer, tester | inquisitor, interrogator | interviewer | canvasser, headcounter, poll taker, pollster.

derivation: ask | query, question | enquire, inquire, investigate | ask, enquire, inquire.