ˈaləˌrän noun
( -s )
Etymology: French, bird's pinion, aileron, diminutive of aile wing, from Latin ala — more at aisle
1. : a half gable or wing wall (as at the end of the aisle of a church)
2. : a movable portion of an airplane wing or a movable airfoil external to the wing that is usually located at the trailing edge near the wing tips and whose function is to impart a rolling motion to the airplane and thus provide lateral control