What ⋊ means
Usually, H is the normal subgroup. In H ⋊ K, K's action transforms H as the groups combine. If that action is trivial, the result is a direct product.
Some authors reverse the convention. Follow the stated action; the hook alone may mislead.
Don't confuse it with
1Questions people ask
1Why can ⋊ look reversed?
It can: Unicode 17.0.0's bidirectional data pairs ⋊ with ⋉; right-to-left layout may display the mirrored glyph while the text stays ⋊.
How to type ⋊
Windows (Word)
Alt+XType 22CA, 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 “right normal factor semidirect product”.
Linux
Ctrl+Shift+UType 22ca, then Enter or Space.
HTML
⋊CSS
\22CALaTeX
Use \rtimes.
HTML
Use ⋊ or ⋊.
Codes and encoding1 code points
HTML decimal
⋊
HTML hex
⋊
CSS content
content: "\22CA";
Each escape is closed by the next backslash; a trailing space is needed before a literal hex digit.
URL encoded
%E2%8B%8A
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.