What is the name of the z axis?

Question

If x is the horizontal axis and y is the vertical axis, then what do you call the z axis that is perpendicular to both x and y? The one that comes directly toward and away from you.

In other words,

width = horizontal

height = vertical

depth = ?

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Please add any tags that fit.

Answer 1

The z-axis, is also sometimes known as.... the z-axis.

If you are drawing the axes as they are typically taught in school, the z-axis becomes the "height", the y-axis is "width" and I guess you could say that the x-axis becomes "depth" or "length"

Answer 2

It's called the Applical axis as it is used for many different applications, as in computer engineering the Applical axis is used as intensity when plotting two wave forms on a Cartesian plane and in physics it's used as depth.