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y-axis

[wahy-ak-sis]
noun, plural y-ax·es [wahy-ak-seez] /ˈwaɪˌæk siz/. Mathematics.
  1. Also called axis of ordinates. (in a plane Cartesian coordinate system) the axis, usually vertical, along which the ordinate is measured and from which the abscissa is measured.
  2. (in a three-dimensional Cartesian coordinate system) the axis along which values of y are measured and at which both x and z equal zero.

Origin of y-axis

First recorded in 1925–30
Can be confusedx-axis y-axis
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for y-axis

y-axis

noun
  1. a reference axis, usually vertical, of a graph or two- or three-dimensional Cartesian coordinate system along which the y- 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
y-axis in Science

y-axis

[wī′ăk′sĭs]
  1. The vertical axis of a two-dimensional Cartesian coordinate system.
  2. One of the three axes of a three-dimensional Cartesian coordinate system.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.