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

Because detailed astronomical measurements of the polar axis location go back to the end of the 19th century, polar drift could enable Seo to trace the human impact on the planet’s water over the past century.

From Science Magazine

In previous studies on interfaces6 and polar crystals7, an intrinsic rectification effect was observed along the plane when a magnetic field was applied perpendicular to both the current and the polar axis.

From Nature

The authors applied a magnetic field perpendicular to the polar axis of the film and observed a superconducting current in a single direction perpendicular to the directions of both the magnetic field and the polar axis.

From Nature

By comparison, the planet Mars sees its polar axis vary by tens of degrees over just a few tens of thousands of years.

From Scientific American

Global warming is changing the way the Earth wobbles on its polar axis, a new Nasa study has found.

From The Guardian