What ⧳ means
In MathML 3, it marks placement, not an operation.
An infix operator sits between the expressions it joins, like a plus sign. This tells a typesetter where ⧳ goes, not what it means in a formula. Use the notation’s definition or diagram key.
Formal math notation; context sets its reading.
“Infix” tells placement, not meaning.
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 ⧳
Windows (Word)
Alt+XType 29F3, 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 “error-barred black circle”.
Linux
Ctrl+Shift+UType 29f3, then Enter or Space.
HTML
⧳CSS
\29F3Codes and encoding1 code points
HTML decimal
⧳
HTML hex
⧳
CSS content
content: "\29F3";
Each escape is closed by the next backslash; a trailing space is needed before a literal hex digit.
URL encoded
%E2%A7%B3
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.