octant

noun
oc·​tant | \ ˈäk-tənt How to pronounce octant (audio) \

Definition of octant

1 : an instrument for observing altitudes of a celestial body from a moving ship or aircraft
2 : any of the eight parts into which a space is divided by three coordinate planes

Examples of octant in a Sentence

Recent Examples on the Web There is no way for such a locus to exist only in opposing octants of a cube. Quanta Magazine, "Solution: ‘The Slippery Math of Causation’," 29 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'octant.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of octant

1672, in the meaning defined at sense 1

History and Etymology for octant

Latin octant-, octans eighth of a circle, from octo

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Time Traveler for octant

The first known use of octant was in 1672

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More from Merriam-Webster on octant

Britannica.com: Encyclopedia article about octant

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