## isopleth

- In common meteorological usage, a line of equal or constant value of a given quantity, with respect to either space or time;
*same as*isogram.

- (
*Also called*isarithm.) A line drawn through points on a graph at which a given quantity has the same numerical value (*or*occurs with the same frequency) as a function of the two coordinate variables.

- A straight line along which lie corresponding values of a dependent and independent variable.

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