octant

noun
oc·tant | \ˈäk-tənt \

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

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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Dictionary Entries near octant

octanol

octanoyl

Octans

octant

octapeptide

octaphyllite

octapla

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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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