Mégas Doúkas Náv̱archos (Greek: Μέγας Δούκας Ναύαρχος, or French: Grand-Duc Admiral) in English it is Grand Duke Admiral or sometimes roughly Lord High Admiral is the ninth rank of the Great Officers of the Realm, being located below the Megas Domestikos. In Diadochia the office is the naval equivalent of the Megas Konostaulos (Grand Constable). The office is now purely ceremonial with the day to day running of the Imperial and Royal Navy being carried out by others.