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

The Azimuth of a star is the angle between the meridian and the vertical circle passing through the star.

From A Text-Book of Astronomy by George C. Comstock

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

These disadvantages are overcome by adding still another graduated circle to the instrument, with its axis perpendicular to the axis of the vertical circle, thus forming a three-circle goniometer.

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

An apparent change in the position of an object, arising from a change of the observer's station, and which diminishes with the altitude of an object in the vertical circle.

From The Sailor's Word-Book An Alphabetical Digest of Nautical Terms, including Some More Especially Military and Scientific, but Useful to Seamen; as well as Archaisms of Early Voyagers, etc. by Sir Edward Belcher