Principal subdivision of a military company, battery, or troop.
Usually commanded by a lieutenant, it consists of 25–50 soldiers organized into two or more squads led by noncommissioned officers. The term was first used in the 17th century to refer to a small body of musketeers who fired together in a volley alternately with another platoon. It has been used in U.S. military manuals since 1779, and throughout the 19th century it meant half a company. It was reintroduced into the British army in 1913. See also military unit .