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Webster 1913 Edition
Rightfulness
Right′ful-ness
,Noun.
 1. 
The quality or state of being rightful; accordance with right and justice. 
2. 
Moral rectitude; righteousness. 
[Obs.] 
Wyclif.
 We fail of perfect 
rightfulness
. Sir P. Sidney.
Webster 1828 Edition
Rightfulness
RIGHTFULNESS
,Noun.
  1.
  Justice; accordance with the rules of right; as the rightfulness of a claim to lands or tenements.2.
  Moral rectitude.But still although we fail of perfect rightfulness.  [Not usual.]