From ProofWiki
Jump to navigation Jump to search


In a cartesian coordinate system, the $y$-axis is the one usually depicted and visualised as going from "bottom" to "top" of the paper (or screen).

It consists of all the points in the real vector space in question (usually either $\R^2$ or $\R^3$) at which all the elements of its coordinates but $y$ are zero.

Also denoted as

Some sources use an abbreviated form to denote the $y$-axis, for example: $\textsf O y$, or $Y'OY$.

Also see

Linguistic Note

The plural of axis is axes, which is pronounced ax-eez not ax-iz.

Compare basis.