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.]
(click for a larger image)aileron
To bank to the left, a pilot must raise the left aileron and lower the right aileron.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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