United States Marine Corps has several ranks which carry the title of Sergeant, the lowest of which is Sergeant (Sgt). Marine Sergeants are the fifth enlisted rank in the U.S. Marine Corps, just above
Corporal and below
Staff Sergeant.
In the Marine Corps, enlisted ranks above Sergeant are referred to as Staff Non-Commissioned Officers (Staff NCOs or SNCOs). These ranks, Staff Sergeant through Sergeant Major, are always referred to by their full rank and never merely as "Sergeant". Gunnery Sergeants are commonly addressed as simply "Gunny" informally.
Master Sergeants are addressed as "Master Sergeant" or "Top" at the preference of the Marine wearing the rank and dependent on the MOS community/culture. This privilege is usually extended to NCOs or SNCOs and above, and even Marines that are the same rank or higher. Master Gunnery Sergeants follow the same protocol but are commonly referred to as "Master Guns" or "Master Gunny."
