A surface having parabolic sections parallel to a single coordinate axis and elliptic or circular sections perpendicular to that axis.
pa·rab′o·loidal (-loidl) adj.
(click for a larger image)paraboloid
The equation for
a paraboloid is
x2/a2 + y2/b2 = z.
If a=b, the paraboloid is circular (as shown above); if not, it is elliptical.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 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:
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