Name given to the third coordinate of a point in a three-dimensional Cartesian coordinate system.

The third axis in a three-dimensional coordinate system is called the *z*-axis.

### Example

In the illustration, the coordinates of point *P* are (1, 3, 2). The *x*-coordinate of point *P* is 1, the *y*‑coordinate is 3 and the *z*-coordinate is 2.