Synonyms for Harmonious (same or very similar meaning)
WordNet sense 1 (involving or characterized by harmony):
consonant
WordNet sense 2 (harmonious in sound):
symphonic, symphonious
WordNet sense 3 (relating to vibrations that occur as a result of vibrations in a nearby body):
harmonic, sympathetic
WordNet sense 4 (exhibiting equivalence or correspondence among constituents of an entity or between different entities):
proportionate, symmetrical
WordNet sense 5 (being in a state of proper balance or equilibrium):
balanced
WordNet sense 6 (suitable and fitting):
appropriate, appropriate
WordNet sense 7 (corresponding in character or kind):
congruent, congruous
WordNet sense 8 (able to exist and perform in harmonious or agreeable combination):
compatible
From the ODE community, based on WordNet
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