The international prohibition sign (official name), also known as a no symbol, no sign, circle - backslash symbol, nay, interdictory circle or universal no, is a red circle with a red diagonal line through it (running from top left to bottom right), completely enclosing a pictogram to indicate something is not permitted. The prohibition sign is sometimes seen in all - black, where color is not available.
what is the symbol of a circle with a line through it called
international prohibition sign