Definition of: aileron

(ā′lə·ron) noun
1. Archit. A wing wall shaped like a scroll to conceal the aisle of a church, or a half-gable formed by a penthouse roof.
2. Aeron. Any of several types of hinged and movable auxiliary surfaces of an airplane, usually located near the trailing edge of a wing and operated by the pilot to give a rolling motion about the longitudinal axis. [<F, dim. of aile wing]