dissonance

noun

1. inharmonious or harsh sound; discord; cacophony.
2. Music.
   1. a simultaneous combination of tones conventionally accepted as being in a state of unrest and needing completion.
   2. an unresolved, discordant chord or interval.Compare consonance(def 3).
3. disagreement or incongruity.

noun

1. a discordant combination of sounds
2. lack of agreement or consistency
3. music
   1. a sensation commonly associated with all intervals of the second and seventh, all diminished and augmented intervals, and all chords based on these intervalsCompare consonance (def. 3)
   2. an interval or chord of this kind