dissimilarity

from WordNet (r) 3.0 (2006)

dissimilarity
    n 1: the quality of being dissimilar [syn: {dissimilarity},
         {unsimilarity}] [ant: {similarity}]

from The Collaborative International Dictionary of English v.0.48

Dissimilarity \Dis*sim`i*lar"i*ty\, n.
   Want of resemblance; unlikeness; dissimilitude; variety; as,
   the dissimilarity of human faces and forms. --Sir W. Jones.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

53 Moby Thesaurus words for "dissimilarity":
      contrariety, contrast, departure, deviation, difference, disaccord,
      disaccordance, disagreement, disconformity, discongruity, discord,
      discordance, discrepancy, discreteness, disparity, dissemblance,
      dissent, dissimilitude, dissonance, distance, distinction,
      distinctness, divarication, divergence, divergency, diversity,
      far cry, heterogeneity, inaccordance, incompatibility, incongruity,
      inconsistency, inconsonance, inequality, inharmoniousness,
      inharmony, irreconcilability, margin, mixture, nonconformity, odds,
      offset, opposition, otherness, separateness, severance,
      unconformity, unlikeness, unorthodoxy, variance, variation,
      variegation, variety