What does the term "trim" refer to in aircraft?

The term "trim" in aircraft refers to the adjustment of control surfaces to relieve control pressures, which is crucial for maintaining stable flight and reducing pilot workload. When trim is applied, it allows the aircraft to fly straight and level without the pilot needing to apply constant force to the control yoke or stick. This adjustment can be made for various control surfaces such as the ailerons, elevator, or rudder, enabling the pilot to achieve a desired flight attitude without continuous control input.

Trimming an aircraft helps ensure that it maintains its desired flight path efficiently, minimizing fatigue during long flights and improving overall comfort. By using trim, a pilot can make fine adjustments to the aircraft's performance, allowing for more precise handling and better responsiveness to flight conditions.