Grand marshal

Common military ranks in English
Navies	Armies	Air forces
Commissioned and Non-commissioned officers
Admiral of the fleet	Marshal or Field marshal	Marshal of the air force
Admiral	General	Air chief marshal
Vice admiral	Lieutenant general	Air marshal
Rear admiral	Major general	Air vice-marshal
Commodore	Brigadier or Brigadier general	Air commodore
Captain	Colonel	Group captain
Commander	Lieutenant colonel	Wing commander
Lieutenant commander	Major or Commandant	Squadron leader
Lieutenant	Captain	Flight lieutenant
Sub-lieutenant	Lieutenant or First lieutenant	Flying officer
Ensign	Second lieutenant	Pilot officer
Midshipman	Officer cadet	Flight cadet
Enlisted grades
Warrant officer or Chief petty officer	Warrant officer or Sergeant major	Warrant officer
Petty officer	Sergeant	Sergeant
Leading seaman	Corporal	Corporal
Seaman	Private	Aircraftman

Grand marshal is a ceremonial, military, or political office of very high rank. The term has its origins with the word "marshal" with the first usage of the term "grand marshal" as a ceremonial title for certain religious orders. The following are some additional usages of the term grand marshal:

As a court title, a grand marshal is normally the supreme court official in a government legislative branch. Some examples include:

Grand marshal often appears as a rank in science fiction sources, often in space or star fleets whose size requires a rank above such other titles as surface marshal and fleet admiral. Among grand marshal science fiction equivalents include:

...
Wikipedia