In modern heraldry, a royal cypher is a monogram or monogram-like device of a country's reigning sovereign, typically consisting of the initials of the monarch's name and title, sometimes interwoven and often surmounted by a crown. Such a cypher as used by an emperor or empress is called an imperial cypher. In the system used by various Commonwealth realms, the title is abbreviated as 'R' for 'rex' or 'regina'. Previously, 'I' stood for 'imperator' or 'imperatrix' of the Indian Empire.
The former Postal Station K in Toronto (pictured in 2006) displays above its main entrance EVIIIR, the royal cypher of King Edward VIII
A Royal Mail post box in Windsor in Berkshire bearing the royal cypher of King Edward VII, an intertwined EVIIR
A Royal Mail vehicle logo used in Scotland during the latter years of the reign of Queen Elizabeth II. A convention adopted after the 1953 Coronation resulted in the EIIR royal cypher not being used in Scotland. The above logo was only used by the Royal Mail in Scotland during Elizabeth's reign, and it features a stylised version of the Crown of Scotland; in the rest of the United Kingdom, St. Edward's Crown was used in the Royal Mail logo during Elizabeth's long reign (1952-2022).
Royal Mail van in Scotland, displaying the Royal Mail logo as used in Scotland during the latter years of the reign of Queen Elizabeth II. Unlike the logo as used in the rest of the United Kingdom during Elizabeth's reign, the Royal Mail logo in Scotland during her reign was surmounted by a stylised version of the Crown of Scotland and did not feature the EIIR royal cypher. This was largely the result of the 'Pillar Box War' of the early 1950s. A stylised version of the Crown of Scotland can be seen on the passenger door of the van as well.
A monogram is a motif made by overlapping or combining two or more letters or other graphemes to form one symbol. Monograms are often made by combining the initials of an individual or a company, used as recognizable symbols or logos. A series of uncombined initials is properly referred to as a cypher and is not a monogram.
The Chi-Rho, a monogram of the first two letters of the Greek word for Christ
Zirkel composed of E, F, V.
Monogram on a ceramic tile, in Paris
Speciedaler of Denmark, bearing the double C7 monogram of Christian VII