Octants

Part of speech: noun

Definitions

1. A division of a three-dimensional space that is created by the intersection of three perpendicular planes
2. a section into which something is divided by these planes
3. one of eight segments formed in a spherical coordinate system by such divisions

Etymology: "Octants" is the plural of "octant", a noun that comes from Latin "octāns", meaning an eighth part, from "octo", eight. The Latin root shows up in many English words built on the number eight, such as "octagon" and "octave". An octant is one eighth of a circle, or one eighth of space divided in a sense of directions around a point. The name fits the shape: a circle split into eight equal sectors gives eight octants. The word is a doublet of "Octans", the name of a faint constellation, so the two English words share a single Latin source but reached English in different forms and senses.