Synonyms for Harmony (same or very similar meaning)
WordNet sense 1 (a harmonious state of things in general and of their properties (as of colors and sounds); congruity of parts with one another and with the whole):
concord, concordance
WordNet sense 2 (the structure of music with respect to the composition and progression of chords):
musical harmony
WordNet sense 3 (compatibility in opinion and action):
harmoniousness
From the ODE community, based on WordNet
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