Circuit (airfield)

An airfield traffic pattern is a standard path followed by aircraft when taking off or landing.At an airport, the pattern (or circuit in the Commonwealth of Nations) is a conventional standard path for coordinating air traffic. It differs from so-called "straight in approaches" and "direct climb outs" in that aircraft using a traffic pattern remain in close proximity to the airport. Patterns are usually employed at small general aviation (GA) airfields and military airbases. Most large airports avoid the system, unless there is GA activity as well as commercial flights. However, a pattern of sorts is used at airports in some cases, such as when an aircraft is required to go around.
See more at Wikipedia.org...