lieutenant

Lieutenant is a commissioned officer rank used in many military forces around the world. In general, lieutenants are junior officers who command or assist in leading smaller units, such as platoons or sections, and who serve under captains or other senior officers. The specific responsibilities and authority of a lieutenant can vary by country, service branch, and operating context.

The term lieutenant comes from Old French lieutenant, meaning a deputy or place holder, from lieu “place” and tenant “holding,” ultimately tracing to Latin roots. The word entered English in the Middle Ages and has been used in military and civil institutions to denote a person who acts in the place of a superior officer.

Rank structure and insignia differ by nation and service. In many armies, there are two grades of lieutenant: a junior lieutenant and a senior lieutenant. For example, in the United States Army, the ranks are second lieutenant (O-1) and first lieutenant (O-2), with insignia of a gold bar for the second lieutenant and a silver bar for the first lieutenant. In the U.S. Navy, the equivalent rank of lieutenant (O-3) is signified by two silver bars. In the United Kingdom and many Commonwealth forces, the sequence commonly includes a second lieutenant (entry-level) and lieutenant thereafter, with insignia that differ from those used on land forces.

Duties typically include leading platoon-sized units, planning and executing missions under the supervision of a captain or major, and serving on staff to develop tactics, training, and operations. The rank is also used in other organizations, such as police and fire services, where a lieutenant functions as a mid-level supervisor responsible for a geographic area or a unit.