A Master Sergeant is the eighth enlisted rank in the United States Marine Corps, just above
Gunnery Sergeant, below
Master Gunnery Sergeant,
Sergeant Major, and
Sergeant Major of the Marine Corps. It is equal in grade to First Sergeant. It is abbreviated as "MSgt." Master Sergeants in the U.S. Marine Corps provide technical leadership as occupational specialists at the E-8 level. General command leadership at this paygrade is provided by the separate rank of First Sergeant.
In the Marine Corps, Master Sergeants may be referred to by the nickname of "Top". This usage is an informal one, however, and would not be used in an official or formal setting. Use of this nickname by Marines of subordinate rank is at the rank holder's discretion.
