What ⃩ means
It bridges the base character in technical notation.
A 2001 Unicode proposal for additional mathematical notation called it the “contraction operator” and said it spans the base. A 2007 Unicode review left it outside the mathematical-symbol property, so that name alone does not make it a general-purpose math operator.
A 2012 Unicode proposal maps a Stokoe wide-bridge mark to this character and glosses it “during.” Stokoe notation was described in 1960 as a system for sign-language dictionaries and research. The proposal also gives different notation extensions for American, British, Italian and Swedish sign languages; “during” is not a universal reading.
How do I type the wide bridge mark?
Add it immediately after the base character.
The mark has no ordinary advance width, so by itself it can look blank or detached. It is meant to stretch across the preceding character, and the font determines how neatly it fits. If it looks wrong, inspect the complete base-plus-mark sequence in a Unicode-aware editor.
Specialist notation; read it in the context of the system using it.
Alone, it may look blank; the bridge needs a base character.
Don't confuse it with
4Questions people ask
1Does the Stokoe wide bridge mean “during”?
No. “During” is the gloss for the mark in one Stokoe notation proposal, not a universal translation. Read the surrounding notation to tell how it functions there.
How to type ⃩
⃩\20E9Codes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.