資料來源 : Webster's Revised Unabridged Dictionary (1913)

Isotonic \I`so*ton"ic\, a. [Iso- + tonic.]
   Having or indicating, equal tones, or tension.

   {Isotonic system} (Mus.), a system consisting of intervals,
      in which each concord is alike tempered, and in which
      there are twelve equal semitones.