The Collaborative International Dictionary of English v.0.48:

Skew \Skew\, a.
   Turned or twisted to one side; situated obliquely; skewed; --
   chiefly used in technical phrases.
   [1913 Webster]

   Skew arch, an oblique arch. See under Oblique.

   Skew back. (Civil Engin.)
   (a) The course of masonry, the stone, or the iron plate,
       having an inclined face, which forms the abutment for the
       voussoirs of a segmental arch.
   (b) A plate, cap, or shoe, having an inclined face to receive
       the nut of a diagonal brace, rod, or the end of an
       inclined strut, in a truss or frame.

   Skew bridge. See under Bridge, n.

   Skew curve (Geom.), a curve of double curvature, or a
      twisted curve. See Plane curve, under Curve.

   Skew gearing, or Skew bevel gearing (Mach.), toothed
      gearing, generally resembling bevel gearing, for
      connecting two shafts that are neither parallel nor
      intersecting, and in which the teeth slant across the
      faces of the gears.

   Skew surface (Geom.), a ruled surface such that in general
      two successive generating straight lines do not intersect;
      a warped surface; as, the helicoid is a skew surface.

   Skew symmetrical determinant (Alg.), a determinant in which
      the elements in each column of the matrix are equal to the
      elements of the corresponding row of the matrix with the
      signs changed, as in (1), below.
      [1913 Webster] (1) 0 2 -3-2 0 53 -5 0 (2) 4 -1 71 8 -2-7 2
      1
      [1913 Webster]

   Note: This requires that the numbers in the diagonal from the
         upper left to lower right corner be zeros. A like
         determinant in which the numbers in the diagonal are
         not zeros is a skew determinant, as in (2), above.
         [1913 Webster]

WordNet (r) 3.0 (2006):

skew arch
    n 1: an arch whose jambs are not at right angles with the face