not counterfeit or copied; "an authentic signature"; "a bona fide manuscript"; "an unquestionable antique"; "photographs taken in a veritable bull ring"
emphasis If you describe something as unquestionable, you are emphasizing that it is so obviously true or real that nobody can doubt it. He inspires affection and respect as a man of unquestionable integrity There is an unquestionable link between job losses and deteriorating services. = undoubted questionable + unquestionably un·ques·tion·ably They have seen the change as unquestionably beneficial to the country He is unquestionably a star