z-axis

American  

[zee-ak-sis] / ˈziˌæk sɪs /

noun

Mathematics.

plural

z-axes

1. (in a three-dimensional Cartesian coordinate system) the axis along which values of z are measured and at which both x and y equal zero.

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z-axis British  

noun

1. a reference axis of a three-dimensional Cartesian coordinate system along which the z- coordinate is measured

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z-axis Scientific  

/ zē′ăk′sĭs /

1. One of the three axes of a three-dimensional Cartesian coordinate system.

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Etymology

Origin of z-axis

First recorded in 1945–50

Example Sentences

He had spent his life building a planar model of his ascent to the presidency, only to get whacked in the head by an unforeseen z-axis.

From Slate • Sep. 27, 2025

Since a single point does not tell us what the shape is, we can move up the z-axis to an arbitrary plane to find the shape of other traces of the figure.

From Textbooks • Mar. 30, 2016

In this case, however, we would likely choose to orient our z-axis with the center axis of the pipeline.

From Textbooks • Mar. 30, 2016

We can then construct a cylinder from the set of lines parallel to the z-axis passing through circle x2 + y2 = 9 in the xy-plane, as shown in the figure.

From Textbooks • Mar. 30, 2016

To represent equations involving three unknowns x, y, z, a third axis is introduced, the z-axis, perpendicular to the plane xy and passing through the intersection of the lines x, y.

From Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 7 "Equation" to "Ethics" by Various