oc·​tant ˈäk-tənt How to pronounce octant (audio)
: an instrument for observing altitudes of a celestial body from a moving ship or aircraft
: 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, 29 June 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'octant.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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

First Known Use

1672, in the meaning defined at sense 1

Time Traveler
The first known use of octant was in 1672

Dictionary Entries Near octant

Cite this Entry

“Octant.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/octant. Accessed 21 Jun. 2024.

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