[ey-luh-ron] 
| 1. | Aeronautics. a movable surface, usually near the trailing edge of a wing, that controls the roll of the airframe or effects maneuvers, as banks and the like. |
| 2. | a wall at the end of a roof with a single slope, as that of a church aisle. |
ai·le·ron (ā'lə-rŏn')  (click for larger image in new window) n. Either of two movable flaps on the wings of an airplane that can be used to control the plane's rolling and banking movements. [French, diminutive of aile, wing, from Old French, from Latin āla.] |
| aileron (ā'lə-rŏn') Pronunciation Key
A hinged surface that is part of the back edge of each wing on an airplane. The ailerons are moved up or down to create uneven lift on the sides of the plane to control its rolling and tilting movements. |
aileron
movable part of an airplane wing that is controlled by the pilot and permits him to roll the aircraft around its longitudinal axis. Ailerons are thus used primarily to bank the aircraft for turning. Ailerons have taken different forms through the years but are usually part of the wing's trailing edge, near the tip. Their efficiency in lateral control made obsolete the Wright brothers' system of wing warping.
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ləˌrɒn