Plain English Meaning

Movable panels on the back edge of the wing, close to the body of the airplane, that the pilot lowers to help the airplane fly more slowly and come down at a steeper angle without speeding up. They are mainly used for takeoff and landing.

Full Definition

Hinged or movable surfaces on the trailing edge of the wing, near the fuselage, that the pilot extends or retracts to change the wing's shape. When extended, flaps increase lift and drag at lower airspeeds, allowing the airplane to fly slower without stalling and to descend more steeply without gaining excess speed. They are typically used during takeoff, approach, and landing.

Context Anchor

You see this term in takeoff, landing, approach, and - discussions, especially when the airplane is being configured to fly slowly.