What ⃛ means
In math: a third time derivative; in Stokoe: curled or flexed fingers.
In calculus and physics, a triple overdot marks a third derivative with respect to time, so x⃛ represents the third rate of change of x. The one-, two-, and three-dot forms belong to Newtonian dot notation. Newton's surviving papers from 1665–1666 use dotted or dashed letters for fluxions, his term for rates of change; the notation was communicated publicly in 1693. In 1960, William Stokoe's notation for sign language used the triple dot for a handshape with curled or flexed fingers. These readings come from separate traditions.
How do I type a triple dot above a letter?
Enter the base first, then the combining mark immediately after it.
In plain text, type x followed immediately by ⃛ to form x⃛. Math editors may offer a triple-overdot command; text input uses the combining mark after the character.
If it appears over a dotted circle or floats alone, the circle is a display aid. The mark needs a preceding character, and fonts and renderers determine how high the dots sit.
Technical and specialized; its documented settings are equations and sign-language notation.
Do not read it as an ellipsis: it attaches above a base and takes meaning from the notation.
What it means when someone sends it to you
2 readingsDon't confuse it with
2Combination ideas
2Questions people ask
2Why is the triple dot floating?
It is a combining mark that needs a preceding base. By itself, a font or renderer may place it beside a dotted circle, leave it floating, or show nothing.
Can I use it in ordinary writing?
You can, but readers may not know its technical reading without a formula or explanation. It fits naturally in calculus notation or Stokoe sign-language writing.
How to type ⃛
⃛\20DBCodes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.