Source : Webster's Revised Unabridged Dictionary (1913)

Silkworm \Silk"worm`\, n. [AS. seolcwyrm.] (Zo["o]l.)
   The larva of any one of numerous species of bombycid moths,
   which spins a large amount of strong silk in constructing its
   cocoon before changing to a pupa.

   Note: The common species ({Bombyx mori}) feeds on the leaves
         of the white mulberry tree. It is native of China, but
         has long been introduced into other countries of Asia
         and Europe, and is reared on a large scale. In America
         it is reared only to small extent. The Ailanthus
         silkworm ({Philosamia cynthia}) is a much larger
         species, of considerable importance, which has been
         introduced into Europe and America from China. The most
         useful American species is the Polyphemus. See
         {Polyphemus}.

   {Pernyi silkworm}, the larva of the Pernyi moth. See {Pernyi
      moth}.

   {Silkworm gut}, a substance prepared from the contents of the
      silk glands of silkworms and used in making lines for
      angling. See {Gut}.

   {Silkworm rot}, a disease of silkworms; muscardine.