from The Century Dictionary.
- noun In rhetoric, the statement of an opponent's objection or of an argument which might be urged against the speaker's or writer's position.
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun rhetoric A
devicein which the author poses a questionwhich is in turn answered.
Sorry, no etymologies found.
And consider Homer's eccentric (or perhaps dyslexic?) use of hypophora (raising questions and answering them): "What's a wedding?