vertical circle

American  

noun

Astronomy.

1. a great circle on the celestial sphere passing through the zenith.

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vertical circle British  

noun

1. astronomy a great circle on the celestial sphere passing through the zenith and perpendicular to the horizon

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vertical circle Scientific  

1. A great circle on the celestial sphere that passes through the zenith and the nadir and thus is perpendicular to the horizon.

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Etymology

Origin of vertical circle

First recorded in 1550–60

Example Sentences

See Examples For:

vertical circle

The flagman swings his lamp, or his flag or hand, in a vertical circle at half-arm's length across the track.

From Time Magazine Archive

A vertical circle is one whose plane is perpendicular to the horizon, hence all such circles must pass through the normal and have the zenith and nadir points for their poles.

From Scientific American Supplement, No. 360, November 25, 1882 by Various

Reflection from an excess of horizontal prisms gives rise to a vertical circle passing through the sun.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 8 "Haller, Albrecht" to "Harmonium" by Various

The horizontal circle of 14-in. diameter is read by three micrometer microscopes; the vertical circle has a diameter of 12 in., and is read by two microscopes.

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6 "Geodesy" to "Geometry" by Various

In these instruments the crystal is set up and adjusted once for all, with the axis of a prominent zone parallel to the axis of either the horizontal or the vertical circle.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 2 "Gloss" to "Gordon, Charles George" by Various