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.]
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