Source : Webster's Revised Unabridged Dictionary (1913)

Resoluteness \Res"o*lute*ness\, n.
   The quality of being resolute.

Source : WordNet®

resoluteness
     n : the trait of being resolute; firmness of purpose; "his
         resoluteness carried him through the battle"; "it was his
         unshakeable resolution to finish the work" [syn: {firmness},
          {resolve}, {resolution}] [ant: {irresoluteness}]