Ailerons

[Sarah]

Plural for [aileron]. Part of an [airplane]'s wing.

[Gregory]

Ailerons in Gliding. Placed on the outer trailing edges of a gliders wings, the control surfaces are used to control the gliders lateral balance and angle of bank.

[Mark Zuckerberg]

a part along the back edge of an aircrafts wing that can be moved to help the aircraft turn or to keep it level