Meaning of OCTANT in English

OCTANT

[ 'ɒkt(ə)nt ]

■ noun

1》 an arc of a circle equal to one eighth of its circumference, or the area enclosed by such an arc with two radii of the circle.

2》 each of eight parts into which a space or solid body is divided by three planes which intersect (especially at right angles) at a single point.

3》 an obsolete instrument in the form of a graduated eighth of a circle, used in astronomy and navigation.

Origin

C17: from L. octans , ~- 'half-quadrant', from octo 'eight'.

Concise Oxford English vocab.      Сжатый оксфордский словарь английского языка.