1.  lambskin(n = noun.substance) - the skin of a lamb with the wool still on;
is a kind of fur, pelt
has particulars: broadtail, persian lamb

2.  lambskin(n = noun.substance) parchment, sheepskin - skin of a sheep or goat prepared for writing on;
is a kind of animal skin
has particulars: vellum

1.  The skin of a lamb; especially, a skin dressed with the wool on, and used as a mat. Also used adjectively. [1913 Webster]

2.  A kind of woolen. [1913 Webster]

lambskin, n. a prepared skin from a lamb with the wool on or as leather.