1. Harsh and inharmonious in sound; discordant.
2. Being at variance; disagreeing.
3. Music Constituting or producing a dissonance.
[Middle English dissonaunt, from Old French dissonant, from Latin dissonāns, dissonant-, present participle of dissonāre, to be dissonant : dis-, apart; see DIS- + sonāre, to sound; see swen- in the Appendix of Indo-European roots.]
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