The Collaborative International Dictionary of English v.0.48:

Awfulness \Aw"ful*ness\, n.
   1. The quality of striking with awe, or with reverence;
      dreadfulness; solemnity; as, the awfulness of this sacred
      place.
      [1913 Webster]

            The awfulness of grandeur.            --Johnson.
      [1913 Webster]

   2. The state of being struck with awe; a spirit of solemnity;
      profound reverence. [Obs.]
      [1913 Webster]

            Producing in us reverence and awfulness. --Jer.
                                                  Taylor.
      [1913 Webster]

WordNet (r) 3.0 (2006):

awfulness
    n 1: a quality of extreme unpleasantness [syn: awfulness,
         dreadfulness, horridness, terribleness]