Synonyms for Dissonant (same or very similar meaning)
WordNet sense 1 (not musical in nature):
unmusical, nonmusical
WordNet sense 2 (characterized by musical dissonance; harmonically unresolved):
unresolved
WordNet sense 3 (lacking in harmony):
discordant, disharmonious, inharmonic
WordNet sense 4 (not in harmony):
unharmonious
From the ODE community, based on WordNet
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