Source : Webster's Revised Unabridged Dictionary (1913)

Paraboloid \Pa*rab"o*loid\ (-loid), n. [Parabola + -oid: cf. F.
   parabolo["i]de.] (Geom.)
   The solid generated by the rotation of a parabola about its
   axis; any surface of the second order whose sections by
   planes parallel to a given line are parabolas.

   Note: The term paraboloid has sometimes been applied also to
         the parabolas of the higher orders. --Hutton.

Source : WordNet®

paraboloid
     n : a surface having parabolic sections parallel to a single
         coordinate axis and elliptic sections perpendicular to
         that axis