pa·rab·o·loid  (pə-răb ə-loid ′)
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n. 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) paraboloidThe 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. |
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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:
Indo-European Roots
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