theodolite

American  

[thee-od-l-ahyt] / θiˈɒd lˌaɪt /

noun

1. Surveying. a precision instrument having a telescopic sight for establishing horizontal and sometimes vertical angles.

2. phototheodolite.

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theodolite British  

/ θɪˈɒdəˌlaɪt, θɪˌɒdəˈlɪtɪk /

noun

1. Also called (in the US and Canada): transit.  a surveying instrument for measuring horizontal and vertical angles, consisting of a small tripod-mounted telescope that is free to move in both the horizontal and vertical planes

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theodolite Scientific  

/ thē-ŏd′l-īt′ /

1. An optical instrument used to measure angles in surveying, meteorology, and navigation. In meteorology, it is used to track the motion of a weather balloon by measuring its elevation and azimuth angle. The earliest theodolite consisted of a small mounted telescope that rotated horizontally and vertically; modern versions are sophisticated computerized devices, capable of tracking weather balloons, airplanes, and other moving objects, at distances of up to 20,000 m (65,600 ft).

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Other Word Forms

• theodolitic
  adjective

Etymology

Origin of theodolite

First recorded in 1565–75, theodolite is from the New Latin word theodolitus < ?

Explanation

Use the noun theodolite to describe the telescope-like tool that surveyors use to precisely measure horizontal and vertical angles in three dimensions. Land surveyors, who measure the distances and angles between points for mapmakers or property owners, are familiar with theodolites. A theodolite is an instrument for measuring angles, especially horizontal ones. The Latin prefix theo, which often means "god," here probably has nothing to do with deities. Theodolite was coined from the Latin theodelitus in the sixteenth century, but even experienced etymologists scratch their heads as to how the word was formed.

Example Sentences

The tool, a theodolite, is used to measure precise geographical location for missile launches as well as the angle and direction of the launchers, Dr Su said.

From BBC • Jan. 4, 2023

Over the city’s center point, Coyote had set up a theodolite, a surveying instrument he used to locate 6,000 small red flags that marked the city’s street grid.

From New York Times • Sep. 5, 2019

Morrison had brought his theodolite, a surveying instrument with a telescope, into Central Park in the early morning and set it up at Belvedere Castle.

From Scientific American • Feb. 15, 2013

Seeing a surveyor pointing a theodolite his way Woodsman Longhini decided it was a cameraman mistaking him for a gangster.

From Time Magazine Archive

On Sunday, April 13, three miles from the mountain’s summit at the Timberline observation station, Swanson peered through a theodolite, an instrument that measured angles very accurately.

From "Mountain of Fire" by Rebecca E. F. Barone