Fan

[1] A fan is a rotating device with curved blades like a propeller. The primary fan in a vehicle is located behind the radiator. Some electric fans may be placed in front of the radiator. It draws air through the radiator so that the coolant looses its heat through the fins of the radiator. It is especially needed when the vehicle is idling or moving slowly. When the vehicle moves quickly, there may be no need for the fan. In some cases, the fan is automatically disengaged. The fan may be driven by a fan belt driven by the engine, or by electricity independent of the engine itself.
[2] Other fans are located throughout the vehicle to push air from one location to another, especially for heating and ventilation.
[3] Radial or axial flow device used for moving or producing flow of gases.
[4] The pattern emitted by a paint spray gun.
See also cooling fan, heater fan, radiator fan motor, radiator fan