Source : Webster's Revised Unabridged Dictionary (1913)

Lambskin \Lamb"skin`\, n.
   1. The skin of a lamb; especially, a skin dressed with the
      wool on, and used as a mat. Also used adjectively.

   2. A kind of woolen.

Source : WordNet®

lambskin
     n 1: the skin of a lamb with the wool still on
     2: skin of a sheep or goat prepared for writing on [syn: {parchment},
         {sheepskin}]