Source : Webster's Revised Unabridged Dictionary (1913)

Blandness \Bland"ness\, n.
   The state or quality of being bland.

Source : WordNet®

blandness
     n 1: the trait of exhibiting no personal embarrassment or
          concern; "the blandness of his confession enraged the
          judge"
     2: lacking any distinctive or interesting taste property [syn:
        {insipidity}, {insipidness}]
     3: smooth and gracious in manner [syn: {suavity}, {suaveness}]