BATTALION, a unit or military organization numbering from 500-1,000 men, the latter figure being usually the standard in modern times. The term is used in nearly every army, and is de rived through Fr. from It. battaglione, Med. Lat. battalia (see BATTLE). "Battalion" in the 16th and 1 7th centuries implied a unit of infantry forming part of the line of battle, but at first meant an unusually large battalia or a single large body of men formed of several battalias. In the British Army the infantry battalion is commanded by a lieut.-colonel, and consists of a headquarter wing and four companies, one of them being a machine-gun company. A similar organization prevails in most foreign armies. Until shortly before the World War the British battalion was divided into eight companies, an inconvenient tactical arrangement, and only in 1928 did the British Army come into line with Continental practice by replacing one of the former four rifle companies by a separate machine-gun company. Machine-gun battalions were formed during the World War, and although discarded since in the British Army, have been revived abroad. Engineers, train, certain kinds of artillery, and more rarely cavalry are also organized in battalions in some coun tries, and tanks universally.