[1] : The Collaborative International Dictionary of English v.0.48

doubtfulness \doubt"fulness\, n.
   1. state of being doubtful.
      1913 webster

   2. uncertainty of meaning; ambiguity; indefiniteness. " the
      doubtfulness of his expressions." --locke.
      1913 webster

   3. uncertainty of event or issue. --bacon.
      1913 webster

[2] : WordNet (r) 2.0

doubtfulness
     n 1: the state of being unsure of something syn: doubt, uncertainty,
           incertitude, dubiety, dubiousness 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,
         dubiousness, question
see also:
doubt uncertainty incertitude dubiety dubiousness certainty 
question 

Doubtfulness >> D Words
Doubtfulness, definition of term: Doubtfulness
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