Source : Webster's Revised Unabridged Dictionary (1913)

Dubiousness \Du"bi*ous*ness\, n.
   State of being dubious.

Source : WordNet®

dubiousness
     n 1: the state of being unsure of something [syn: {doubt}, {uncertainty},
           {incertitude}, {dubiety}, {doubtfulness}] [ant: {certainty}]
     2: uncertainty about the truth or factuality of existence of
        something; "the dubiousness of his claim"; "there is no
        question about the validity of the enterprise" [syn: {doubt},
         {doubtfulness}, {question}]