What ⬻ means
It marks a leftward relationship; the surrounding notation defines which one. Read the expression around it to see what objects it connects and what the author intends.
Unicode accepted ⬻ in 2006 as part of a group of mathematical arrows proposed to fill gaps in the existing repertoire. The proposal aimed to add opposite-direction forms where an arrow had previously been encoded only one way.
Don't confuse it with
4⬼⬽⬴⬵
Leftwards Two-Headed Arrow With Tail With Vertical Stroke
shares “arrow”, “headed”, “leftwards”, “tail”, “two”
Leftwards Two-Headed Arrow With Tail With Double Vertical Stroke
shares “arrow”, “headed”, “leftwards”, “tail”, “two”
Leftwards Two-Headed Arrow With Vertical Stroke
shares “arrow”, “headed”, “leftwards”, “two”
Leftwards Two-Headed Arrow With Double Vertical Stroke
shares “arrow”, “headed”, “leftwards”, “two”
Questions 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 2B3B, 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 “leftwards two-headed arrow with tail”.
Linux
Ctrl+Shift+UType 2b3b, then Enter or Space.
HTML
⬻CSS
\2B3BCodes and encoding1 code points
HTML decimal
⬻
HTML hex
⬻
CSS content
content: "\2B3B";
Each escape is closed by the next backslash; a trailing space is needed before a literal hex digit.
URL encoded
%E2%AC%BB
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.