Source : Webster's Revised Unabridged Dictionary (1913)

Undoubted \Un*doubt"ed\, a.
   Not doubted; not called in question; indubitable;
   indisputable; as, undoubted proof; undoubted hero. --
   {Un*doubt"ed*ly}, adv.

Source : WordNet®

undoubted
     adj : accepted without question; "undoubted evidence" [syn: {unchallenged},
            {undisputed}, {unquestioned}]