Field officer rank category (OF-3 to OF-5) of the Russian Imperial Army and Navy until 1917. The British Army (in which these officers are called officers of field rank), and some others in the Commonwealth (including the Australian Army and New Zealand Army), also include the brigadier in this category: the equivalent in other armies is a general officer (the brigadier general). Today, a field officer in the United States (here called field grade) Army, Marine Corps, and Air Force is typically a major, lieutenant colonel, or a colonel: Field officer A field officer, field-grade officer, or senior officer is an army,
Major (United States) Major (United States) In the United States Army, Marine Corps, and Air Force, major is a field grade military officer rank above the rank of captain and below the rank of lieutenant colonel. It is equivalent to the naval rank of lieutenant commander in the other uniformed services. Although lieutenant commanders are considered junior officers by their respective services, the rank of major is considered field grade in the United States Army and the United States Marine Corps. The pay grade for the rank of major is O-4. The insignia for the rank consists of a golden oak leaf, with