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x-axis

American  
[eks-ak-sis] / ˈɛksˌæk sɪs /

noun

Mathematics.

plural

x-axes
  1. Also called axis of abscissas.  (in a plane Cartesian coordinate system) the axis, usually horizontal, along which the abscissa is measured and from which the ordinate is measured.

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


x-axis British  

noun

  1. a reference axis, usually horizontal, of a graph or two- or three-dimensional Cartesian coordinate system along which the x- coordinate is measured

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

x-axis Scientific  
/ ĕksăk′sĭs /
  1. The horizontal axis of a two-dimensional Cartesian coordinate system.

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


Etymology

Origin of x-axis

First recorded in 1925–30

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The angle between i and the x-axis is 90 degrees.

From Literature

In May, the governor’s office apologized after a graph was posted showing a downward trajectory of cases — but only because the x-axis was not in chronological order.

From Washington Post

For example, in the parabola y = x² – 4x – 5 the two solutions when y = 0 are the symmetrical points r and s, where the parabola crosses the x-axis.

From Seattle Times

The x-axis is effort; the y-axis is results.

From Seattle Times

We now take for granted graphs that have one variable on the x-axis and the other on the y; back then, it wasn’t obvious that you could plot equations in this way.

From Nature