The Collaborative International Dictionary of English v.0.48:

Harmony \Har"mo*ny\ (h[aum]r"m[-o]*n[y^]), n.; pl. Harmonies
   (-n[i^]z). [F. harmonie, L. harmonia, Gr. "armoni`a joint,
   proportion, concord, fr. "armo`s a fitting or joining. See
   Article.]
   1. The just adaptation of parts to each other, in any system
      or combination of things, or in things intended to form a
      connected whole; such an agreement between the different
      parts of a design or composition as to produce unity of
      effect; as, the harmony of the universe.
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   2. Concord or agreement in facts, opinions, manners,
      interests, etc.; good correspondence; peace and
      friendship; as, good citizens live in harmony.
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   3. A literary work which brings together or arranges
      systematically parallel passages of historians respecting
      the same events, and shows their agreement or consistency;
      as, a harmony of the Gospels.
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   4. (Mus.)
      (a) A succession of chords according to the rules of
          progression and modulation.
      (b) The science which treats of their construction and
          progression.
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                Ten thousand harps, that tuned
                Angelic harmonies.                --Milton.
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   5. (Anat.) See Harmonic suture, under Harmonic.
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   Close harmony, Dispersed harmony, etc. See under Close,
      Dispersed, etc.

   Harmony of the spheres. See Music of the spheres, under
      Music.

   Syn: Harmony, Melody.

   Usage: Harmony results from the concord of two or more
          strains or sounds which differ in pitch and quality.
          Melody denotes the pleasing alternation and variety of
          musical and measured sounds, as they succeed each
          other in a single verse or strain.
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