Is it ensure, insure, or assure?
1878, shortening of graphic formula (see graphic). The verb meaning "charted on a graph" is from 1889. Related: Graphed; graphing.
A diagram showing the relationship of quantities, especially such a diagram in which lines, bars, or proportional areas represent how one quantity depends on or changes with another.
A curve or line showing a mathematical function or equation, typically drawn in a Cartesian coordinate system. The graph of the function y = x2 is a parabola.