Major, in the Army, is the lowest rank of field-officer. There are two on the establishment of every infantry battalion in the British army and three on that of each cavalry regiment, one in command of each battery of artillery, about 150 in the engineers—promoted after twenty years' service whether vacancies exist or not—15 in the Royal Marine Artillery, and 42 in the Royal Marine Light Infantry. Previous to 1872 the majors of artillery and engineers were called first-captains. The duties of majors of infantry in the field, where they are always mounted, are generally to take up points on which the line is dressed and to command, one the supports, and the other the reserve in attack formation. In barracks they assist the commanding officer in all matters of interior economy and discipline. Cavalry majors perform similar duties, except that in the field each commands a squadron. In garrison all regimental majors and captains who for distinguished service have been given brevet rank as majors take their turn as president of district courts-martial and as field-officer of the day, attending guard-mounting, visiting the guards by day and night, taking command of picquets in case of fire, riot, or alarm, &c. The pay of a major ranges from 16s. a day in the infantry of the line to £1, 4s. 5d. in the household cavalry. In the United States army the yearly pay of a major is $2500.
The word major is used also in conjunction with other military titles, thus: major-general is the lowest rank of General (q.v.); surgeon-major is the rank next above surgeon; a sergeant-major is a staff-sergeant superior to a sergeant; drum-major, trumpet-major, farrier-major, &c. are the old titles of the sergeant-drummers, sergeant-trumpeters, sergeant-farriers, &c. A corporal-major in the household cavalry corresponds to the regimental sergeant-major or senior non-commissioned officer in other corps.