The Collaborative International Dictionary of English v.0.48:

Carding \Card"ing\, a.
   1. The act or process of preparing staple for spinning, etc.,
      by carding it. See the Note under Card, v. t.
      [1913 Webster]

   2. A roll of wool or other fiber as it comes from the carding
      machine.
      [1913 Webster]

   Carding engine, Carding machine, a machine for carding
      cotton, wool, or other fiber, by subjecting it to the
      action of cylinders, or drums covered with wire-toothed
      cards, revolving nearly in contact with each other, at
      different rates of speed, or in opposite directions. The
      staple issues in soft sheets, or in slender rolls called
      slivers.
      [1913 Webster]