paraboloidThe equation for a circular paraboloid is x2/a2 + y2/b2 = z.pa·rab·o·loid (p?-r?b??-loid?)n. A surface having parabolic sections parallel to a single coordinate axis and elliptic or circular sections perpendicular to that axis.pa·rab?o·loi?dal (-loid?l) adj.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.paraboloid (p??ræb??l??d) n (Mathematics) a geometric surface whose sections parallel to two coordinate planes are parabolic and whose sections parallel to the third plane are either elliptical or hyperbolic. Equations x2/a2 ± y2/b2 = 2cz pa?rabo?loidal adjCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014pa?rab?o?loid (p??ræb ??l??d) n. a surface that can be put into a position such that its sections parallel to at least one coordinate plane are parabolas. [1650?60] pa?rab`o?loi?dal, adj. Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.