Master Chief Petty Officer of the Navy

Master Chief Petty Officer is the tenth and highest enlisted rank of the UNSC Navy and is a non-commissioned officer. It is equal in rank to Sergeant Major of the Marine Corps in the UNSC Marine Corps.

In informal settings, Master Chief Petty Officers are typically called "Master Chief" or "Chief".

The protagonist of the Halo series, "Master Chief", is named for his rank of Master Chief Petty Officer of the Navy.