Definitions for "Isoline"
(See Isopleth)
a line through points of equal value.
A line connecting points of equal value. De Blij, H. J., and Perter O. Muller; Geography - Regions and Concepts; John Wiley and Sons, Inc.; New York, Chichester, Brisbane, Toronto and Singapore; 1992; page 606.
a result of the intersection between an isovalue horizontal plane and the relief
a curve parameterized by one of the surface parameters while the other surface parameter is fixed