iso·ton·ic /ˌaɪsəˈtɑnɪk/
  (a.)等滲的,等張的,等壓的
  iso·ton·ic /ˌaɪsəˈtɑnɪk/ 形容詞
  I·so·ton·ic a.
  1. Having or indicating, equal tones, or tension.
     A knowledge of the colligative properties of solutions . . . is essential for one to understand fully the principles involved in rendering intravenous solutions isotonic with blood serum, or opthalmic solutions isotonic with lachrymal fluid.  Solutions thus adjusted produce less shock and much less irritation than those which are hypotonic or hypertonic, and present-day practise recognizes the desirability of making the necessary adjustments whenever possible.   --Cook & Martin (Remington's Practice of Pharmacy, Tenth Ed.: Mack Publ., Easton Pa., 1951)
  Isotonic system Mus., a system consisting of intervals, in which each concord is alike tempered, and in which there are twelve equal semitones.
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  isotonic
       adj 1: (used of solutions) having the same or equal osmotic
              pressure [syn: isosmotic] [ant: hypertonic, hypotonic]
       2: relating to or characterized by the equal intervals of the
          well-tempered scale; "isotonic tuning"
       3: of or involving muscular contraction in which tension is
          constant while length changes [ant: isometric]
       4: of two or more muscles; having equal tension