Cartesian Coordinate Definition

noun

A member of the set of numbers that locates a point in a Cartesian coordinate system.

American Heritage

(geometry) The coordinates of a point measured from an origin along a horizontal axis from left to right (the x-axis) and along a vertical axis from bottom to top (the y-axis). This can be extended to three-dimensions by the z-axis perpendicular to the x- and y-axes.

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