Royal dukedoms in the United Kingdom
In the British peerage, a royal duke is a member of the British royal family, entitled to the titular dignity of prince and the style of "His Royal Highness" who holds a dukedom. Dukedoms are the highest titles in the British roll of peerage and the holders of these particular dukedoms are Princes of the Blood Royal. The holders of the dukedoms are royal not the titles themselves. They are titles created and bestowed on legitimate sons and male-line grandsons of the British monarch, usually upon reaching their majority or marriage. The titles can be inherited but cease to be called "royal" once they pass beyond the grandsons of a monarch. As with any peerage, once the title becomes extinct, it may subsequently be recreated by the reigning monarch at any time.
Grandee
Grandee (; , ; , ) is an official aristocratic title conferred on some Spanish nobility and, to a lesser extent, Portuguese nobility. Holders of this dignity enjoyed similar privileges to those of the peerage of France during the Ancien Régime, but unlike in Great Britain, they were not organised into political groupings. "Grandee of Spain" is the highest dignity of nobility in all of Europe, due to its privileges having been greater than those of other similar European dignities, such as the peers of France or the peers of Great Britain. All Dukedoms are automatically attached to a Grandeeship yet only a few Marquessates, Countships, Viscountcies, Baronies and Lordships have the distinction. A single person can be a Grandee of Spain multiple times, as Grandeeships are attached, with the exception of a few cases, to a title and not an individual. Consequently, nobles in Spain with more than one title, most notably the Duchess of Medinaceli and the Duke of Alba, are Grandees 10 and 9 times respectively.