Isodiabatic lines

from The Collaborative International Dictionary of English v.0.48
Isodiabatic \I`so*di`a*bat"ic\, a. [Iso- + Gr. ? to pass
   through.] (Physics)
   Pertaining to the reception or the giving out of equal
   quantities of heat by a substance. --Rankine.
   [1913 Webster]

   {Isodiabatic lines} or {Isodiabatic curves}, a pair of lines
      or curves exhibiting, on a diagram of energy, the law of
      variation of the pressure and density of a fluid, the one
      during the lowering, and the other during the raising, of
      its temperature, when the quantity of heat given out by
      the fluid during any given stage of the one process is
      equal to the quantity received during the corresponding
      stage of the other. Such lines are said to be isodiabatic
      with respect to each other. Compare {Adiabatic}.
      [1913 Webster]
    

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