Majesty is an English word from the Latin: maiestas, meaning greatness. It is a style of address. It is often used when directly addressing or referring to a monarch. The plural form is Their Majesties. The style ranks above Royal Highness.
↑Ambassador Mary Mel French, United States Protocol: The Guide to Official Diplomatic Etiquette (Lanham, MD: Rowman & Littlefield Publishers, Inc., 2010), p. 116