Quartermaster, a term applied to certain officers in both the army and navy.

In armies a quartermaster buys, stores, and transports clothing, food, tents, fuel, medicine, and other supplies. (Fighting equipment—weapons and ammunition—is supplied by ordnance officers.) In the field, the quartermaster marks out the camp and superintends the assignment of quarters and distribution of clothing, fuel, and rations. In permanent quarters the quartermaster has charge of the barracks, mess halls, and other buildings. In the U.S. Army, the Quartermaster Corps is also responsible for maintaining national cemeteries and providing for burial of soldiers. Quartermasters are officers actually assigned to the Quartermaster Corps; officers who perform some of the same functions for small units are called supply officers.

In the navy, quartermasters are usually petty officers. Their duty when at sea is to make sure that the helmsmen keep the ship on its proper course and that all orders from the officer of the watch affecting the movements of the helm are carried out. They are also responsible for correcting and storing charts, for maintaining navigation aids, and for sending and receiving messages by blinker or other visual means.