椭球坐标系是一种三维正交坐标系，是椭圆坐标系的推广。与大多数的三维正交坐标系的生成方法不同，椭球坐标系不是由任何二维正交坐标系延伸或旋转生成的。

椭球坐标 以直角坐标 定义为：

其中，椭球坐标遵守以下限制：

Ellipsoidal coordinates are a three-dimensional orthogonal coordinate system that generalizes the two-dimensional elliptic coordinate system. Unlike most three-dimensional orthogonal coordinate systems that feature quadratic coordinate surfaces, the ellipsoidal coordinate system is not produced by rotating or projecting any two-dimensional orthogonal coordinate system.