No symbol

This article is about the graphic symbol used to denote prohibition. For the Japanese kana, see No (kana). For the № symbol, see Numero sign.
The ISO 3864-1 prohibition sign

The general prohibition sign,[1] also known informally as the no symbol, 'do not' sign, circle-backslash symbol, nay, interdictory circle, prohibited symbol, don't do it symbol, or universal no, is a red circle with a 45-degree diagonal line inside the circle from upper-left to lower-right. It is typically overlaid on a pictogram to warn that an activity is not permitted, or has accompanying text to describe what is prohibited.

  1. ^ "ISO Symbol P001: General prohibition sign". www.iso.org. Retrieved 2019-03-17.