The Collaborative International Dictionary of English v.0.48:

Unaffected \Un`af*fect"ed\, a.
   1. Not affected or moved; destitute of affection or emotion;
      uninfluenced.
      [1913 Webster]

            A poor, cold, unspirited, unmannered,
            Unhonest, unaffected, undone fool.    --J. Fletcher.
      [1913 Webster]

   2. Free from affectation; plain; simple; natural; real;
      sincere; genuine; as, unaffected sorrow.
      [1913 Webster] -- Un`af*fect"ed*ly, adv. --
      Un`af*fect"ed*ness, n.
      [1913 Webster]

WordNet (r) 3.0 (2006):

unaffectedness
    n 1: not affected; a personal manner that is not consciously
         constrained [ant: affectedness]