What ◙ means
It showed the line-feed control character.
Code Page 437, a character set for early IBM PCs, used ◙ as the visible glyph for control value 0A, the line-feed instruction that moves text to the next line. A Unicode proposal about terminal graphics in 1998 lists this mapping among PC control-code pictures—symbols that let a terminal (a text-only computer display) show instructions that normally do not print.
Don't confuse it with
1Questions 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 ◙
Windows (Word)
Alt+XType 25D9, then Alt+X to get ◙.
Windows
Win+Rrun charmap for the full table, or use the emoji picker's Ω symbols tab (Win + .).
macOS
Control+Command+SpaceOpen the character viewer and search “inverse white circle”.
Linux
Ctrl+Shift+UType 25d9, then Enter or Space.
HTML
◙CSS
\25D9Codes and encoding1 code points
HTML decimal
◙
HTML hex
◙
CSS content
content: "\25D9";
Each escape is closed by the next backslash; a trailing space is needed before a literal hex digit.
URL encoded
%E2%97%99
1
On screen
1
Code points
1
JS .length
3
UTF-8 bytes
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.