A high-ranking noble title in European and Japanese peerage systems. In Japanese history, it was the highest of the five ranks (五等爵) established in the Meiji era. When referring to British royalty, 'prince' may be used for certain dukes, but the primary equivalent is 'duke'.
See also: 五等爵
He holds the title of duke.
The Duke of Edinburgh is a member of the British royal family.
He was made a duke in recognition of his achievements.
The eldest son succeeded to the dukedom after his father's death.