No symbol

The no symbol (also known as a prohibition sign, no sign, circle-backslash symbol, nay, interdictory circle, or universal no) is a circle with a diagonal line through it (running from top left to bottom right), surrounding a pictogram used to indicate something is not permitted. The no symbol is generally colored red, but is sometimes another color, typically black.

The Unicode code point for the prohibition sign (also called the no symbol) is U+20E0, Combining Enclosing Circle Backslash (   ⃠   ). It is a combining character, which means that it appears on top of the character before it, so putting d⃠ will show   d⃠.  . (Note: This will appear only if the character exists in an available font.) It also appears in the Webdings and Wingdings 2 fonts.

There is also a prohibition sign emoji located at U+1F6AB NO ENTRY SIGN (...
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