1. Having the shape of a spheroid generated by rotating an ellipse about its longer axis.
2. Having the distance between the poles longer than the equatorial diameter: a prolate spheroid.
[Latin prōlātus, past participle of prōferre, to stretch out : prō-, forth; see PRO-1 + lātus, brought; see telə- in the Appendix of Indo-European roots.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. 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.