Bat‐tal″ion (?), n.(Mil.) An infantry command of two or more companies, which is the tactical unit of the infantry, or the smallest command which is self-supporting upon the battlefield, and also the unit in which the strength of the infantry of an army is expressed.
☞ In the United States army, since April 29, 1898, a battalion consists of four companies, and three battalions form a regiment. The term is also applied to two or more batteries of artillery combined into a single command.