polar axis

American  

noun

Mathematics.

1. the fixed line, usually horizontal, from which the angle made by the radius vector is measured in a polar coordinate system.

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polar axis British  

noun

1. the fixed line in a system of polar coordinates from which the polar angle, θ, is measured anticlockwise

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Etymology

Origin of polar axis

First recorded in 1890–95

Example Sentences

The directrix will be parallel to the polar axis.

From Textbooks • Dec. 21, 2021

Find the area of the region D bounded by the polar axis and the upper half of the cardioid r = 1 + cos θ.

From Textbooks • Mar. 30, 2016

For the following exercises, convert the equation from rectangular to polar form and graph on the polar axis.

From Textbooks • Feb. 13, 2015

This point is also the only polar axis intercept.

From Textbooks • Feb. 13, 2015

Generally, if constrained to move in any other plane, the axis seeks the position nearest to the polar axis, like a dipping needle with respect to the magnetic pole.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 7 "Gyantse" to "Hallel" by Various