quadric surface
locus of zeros of a quadratic polynomial in a three-dimensional space (affine or projective, not necessarily real)
en-GB/kwɒdɹɪk ˈsɜːfɪs/
en-US/ˈkwɑdɹɪk ˈsɝfɪs/
locus of zeros of a quadratic polynomial in a three-dimensional space (affine or projective, not necessarily real)