What means
It names the three filled pieces in the eight-part tile. An octant is one of eight parts of a cell, arranged two across and four down. A 1983 manual for the Kaypro 10, a personal computer of its era, describes eight controllable pixels in each text cell; programs used these cells together to draw simple pictures on a text screen.
A Unicode proposal from 2021 carried the Kaypro patterns into Unicode for converting legacy data, emulators, and text-mode graphics. The tile shifted from machine-specific drawing material to a shared, reusable character.
Don't confuse it with
4Questions people ask
1Why does show as a box on some devices?
Because that device's fonts have no glyph for it. The character is still correct and still copies correctly — the box is a missing glyph, not a broken character.
How to type
𜴎\1CD0ECodes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.