What ⃘ means
It marks an integral as running around a closed path.
A reported 1901 use by Wilson places a small circle on an integral for a closed-curve calculation; that is an early attestation, not proof of one inventor. The Unicode 1.0 name index gives the older label “RING OVERLAY, NON-SPACING.”
Unicode's math archive describes this as a combining part for contour, surface, and volume integral signs. A contour integral follows a path; double and triple integrals extend the notation to surface and volume calculations.
Why does ⃘ look broken by itself?
It needs a preceding character to sit on.
Combining marks attach to the character before them and have no spacing of their own. Without a base, a font may place ⃘ awkwardly or show a dotted-circle placeholder; the placeholder is not part of the text.
How do I type ⃘ after an integral?
Put the mark after its base character.
Use that base-first order in a sequence such as , , or . In code or HTML, put the mark's input form after the base character.
Technical mathematical notation; its reading depends on the preceding integral.
Alone, it does not make a readable circle.
Don't confuse it with
1
Related characters
2
Combination ideas
3Questions 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.
More like this
10
Collections with ⃘
2
How to type or find ⃘
- Also called
- non-spacing ring overlay
- Search it as
- u20d8 · 20d8 · ring overlay · combining mark · contour integral · closed integral · surface integral · volume integral
- Shows up in
- Anything that takes text · its shape is whatever your font draws
⃘\20D8Codes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.