In aeronautics and aviation, loiter is a phase of flight. The phase consists of cruising for a certain amount of time over a small region. The loiter phase occurs, for general aviation, generally at the end of the flight plan, normally when the plane is waiting for clearance to land.
In military flights, such as aerial reconnaissance or ground-attack aircraft, the loiter phase is time the aircraft has over a target. Cruise is the time period the aircraft travels to the target and returns after the loiter.
In astronautics, the loiter phase of spacecraft used for human spaceflight may be as long as six months, as is the case for Soyuz spacecraft which remain docked while expedition crewmembers reside aboard the International Space Station.