sextant

[ sek-stuhnt ]

noun

1. an astronomical instrument used to determine latitude and longitude at sea by measuring angular distances, especially the altitudes of sun, moon, and stars.
2. Sextant, Astronomy. the constellation Sextans.

sextant

/ ˈsɛkstənt /

noun

1. an optical instrument used in navigation and consisting of a telescope through which a sighting of a heavenly body is taken, with protractors for determining its angular distance above the horizon or from another heavenly body
2. a sixth part of a circle having an arc which subtends an angle of 60°

sextant

/ sĕk′stənt /

1. An instrument containing a graduated 60° arc and a movable pivoted arm corresponding to the radius of the arc's circle, used in celestial navigation to measure the altitude of a celestial body in order to determine the observer's latitude and longitude. A horizontally mounted telescope and two small mirrors are arranged so that the observer can, by moving the pivoted arm, sight the horizon and the reflected image of the celestial body in the same line, giving a reading along the arc that is used to look up the observer's position in a published table.

Word History and Origins

Origin of sextant¹

First recorded in 1590–1600; from Latin sextant- (stem of sextāns ) sixth part of a unit; sext ¹, -ant

Word History and Origins

Origin of sextant¹

C17: from Latin sextāns one sixth of a unit

Example Sentences

Again, however, the clock was ticking, and Bound had to decide how much faith to put in coordinates recorded by Worsley at a time when a whiteout had been obscuring the horizon — a necessary reference point for an accurate sextant reading.

From Washington Post

Now Marina had to hold her sextant out of the hatch of her cabin into the icy wind so she could calculate which direction they should fly.

From Literature

The next morning, after 16 hours of flying with only a compass and sextant for direction, the pair spotted land.

From Washington Post

Using an instrument called a sextant, the navigator can measure the height of the star above the horizon.

From Literature

Armed with sextant, chronometers, compass, and nautical tables, Frank Worsley, skipper of Endurance, had been able to calculate and plot their every position.

From Literature