First lieutenant

First lieutenant is a commissioned officer military rank in many armed forces; in some forces, it is an appointment.

The rank of lieutenant has different meanings in different military formations, but in most forces it is sub-divided into a senior (first lieutenant) and junior (second lieutenant) rank. The NATO equivalent rank for land force officers is OF-1 rank. In navies, while certain rank insignia may carry the name lieutenant, the term may also be used to relate to a particular post or duty, rather than a rank.