au·to·gi·ro also au·to·gy·ro (ô′tō-jīrō)
n. pl. au·to·gi·ros also au·to·gy·ros
An aircraft powered by a conventional propeller and supported in flight by a freewheeling, horizontal rotor that provides lift.
[Originally a trademark.]
(click for a larger image)autogiro
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:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.