The Collaborative International Dictionary
Unanswerableness
Unanswerable \Un*an"swer*a*ble\, a. Not answerable; irrefutable; conclusive; decisive; as, he have an unanswerable argument. -- Un*an"swer*a*ble*ness, n. -- Un*an"swer*a*bly, adv.
Wiktionary
unanswerableness
n. The state of being unanswerable.