What ∔ means
The plus sign with a dot above does not fix the operation.
Read the author's definition.
One textbook uses ∔ to combine algebras—structures with addition and multiplication—into a product.
Dot plus versus direct sum?
They can mean different constructions.
In that book, ⊕ marks the direct sum of modules, which combines them while keeping their parts distinct; a module supports scalar multiplication by elements of a ring.
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 2214, 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 “dot plus”.
Linux
Ctrl+Shift+UType 2214, then Enter or Space.
HTML
∔CSS
\2214LaTeX
In math mode, write `\dotplus`.
HTML
Use `∔` or `∔` in HTML.
Codes and encoding1 code points
HTML decimal
∔
HTML hex
∔
CSS content
content: "\2214";
Each escape is closed by the next backslash; a trailing space is needed before a literal hex digit.
URL encoded
%E2%88%94
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.