[1] : The Collaborative International Dictionary of English v.0.48

dissonance \dis"sonance\, n. l. dissonantia: cf. f.
   dissonance.
   1. a mingling of discordant sounds; an inharmonious
      combination of sounds; discord.
      1913 webster

            filled the air with barbarous dissonance. --milton.
      1913 webster

   2. want of agreement; incongruity. --milton.
      1913 webster

[2] : WordNet (r) 2.0

dissonance
     n 1: a conflict of people's opinions or actions or characters
          syn: disagreement, dissension ant: agreement
     2: the auditory experience of sound that lacks musical quality;
        sound that is a disagreeable auditory experience; "modern
        music is just noise to me" syn: noise, racket
     3: disagreeable sounds ant: harmony
see also:
disagreement dissension agreement noise racket harmony 

[3] : Moby Thesaurus II by Grady Ward, 1.0

82 moby thesaurus words for "dissonance":
   antagonism, argumentation, atonalism, atonality, cacophony,
   clashing, clinker, conflict, contention, contradiction,
   contrariety, contrast, controversy, departure, deviation,
   difference, disaccord, disaccordance, disagreement, disconformity,
   discongruity, discord, discordance, discordancy, discrepancy,
   discreteness, disharmony, disparity, dissension, dissent,
   dissidence, dissimilarity, dissonancy, dissonant chord,
   distinction, distinctness, disunion, disunity, divergence,
   divergency, diversity, faction, far cry, flatness, heterogeneity,
   inaccordance, incompatibility, incongruity, inconsistency,
   inconsonance, inequality, inharmoniousness, inharmony,
   irreconcilability, jarring, mixture, negation, nonconformity, odds,
   off note, opposition, oppugnancy, otherness, repugnance,
   separateness, sharpness, sour note, sourness, stridor, strife,
   tunelessness, unconformity, unharmoniousness, unlikeness,
   unmusicality, unorthodoxy, untunefulness, variance, variation,
   variegation, variety, wolf

Dissonance >> D Words
Dissonance, definition of term: Dissonance
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