Source : Webster's Revised Unabridged Dictionary (1913)

Silk \Silk\, n. [OE. silk, selk, AS. seolc, seoloc; akin to
   Icel. silki, SW. & Dan. silke; prob. through Slavic from an
   Oriental source; cf. Lith. szilkai, Russ. shelk', and also L.
   sericum Seric stuff, silk. Cf. {Sericeous}. {Serge} a woolen
   stuff.]
   1. The fine, soft thread produced by various species of
      caterpillars in forming the cocoons within which the worm
      is inclosed during the pupa state, especially that
      produced by the larv[ae] of {Bombyx mori}.

   2. Hence, thread spun, or cloth woven, from the above-named
      material.

   3. That which resembles silk, as the filiform styles of the
      female flower of maize.

   {Raw silk}, silk as it is wound off from the cocoons, and
      before it is manufactured.

   {Silk cotton}, a cottony substance enveloping the seeds of
      the silk-cotton tree.

   {Silk-cotton tree} (Bot.), a name for several tropical trees
      of the genera {Bombax} and {Eriodendron}, and belonging to
      the order {Bombace[ae]}. The trees grow to an immense
      size, and have their seeds enveloped in a cottony
      substance, which is used for stuffing cushions, but can
      not be spun.

   {Silk flower}. (Bot.)
      (a) The silk tree.
      (b) A similar tree ({Calliandra trinervia}) of Peru.

   {Silk fowl} (Zo["o]l.), a breed of domestic fowls having
      silky plumage.

   {Silk gland} (Zo["o]l.), a gland which secretes the material
      of silk, as in spider or a silkworm; a sericterium.

   {Silk gown}, the distinctive robe of a barrister who has been
      appointed king's or queen's counsel; hence, the counsel
      himself. Such a one has precedence over mere barristers,
      who wear stuff gowns. [Eng.]

   {Silk grass} (Bot.), a kind of grass ({Stipa comata}) of the
      Western United States, which has very long silky awns. The
      name is also sometimes given to various species of the
      genera {Aqave} and {Yucca}.

   {Silk moth} (Zo["o]l.), the adult moth of any silkworm. See
      {Silkworm}.

   {Silk shag}, a coarse, rough-woven silk, like plush, but with
      a stiffer nap.

   {Silk spider} (Zo["o]l.), a large spider ({Nephila
      plumipes}), native of the Southern United States,
      remarkable for the large quantity of strong silk it
      produces and for the great disparity in the sizes of the
      sexes.

   {Silk thrower}, {Silk throwster}, one who twists or spins
      silk, and prepares it for weaving. --Brande & C.

   {Silk tree} (Bot.), an Asiatic leguminous tree ({Albizzia
      Julibrissin}) with finely bipinnate leaves, and large flat
      pods; -- so called because of the abundant long silky
      stamens of its blossoms. Also called {silk flower}.

   {Silk vessel}. (Zo["o]l.) Same as {Silk gland}, above.

   {Virginia silk} (Bot.), a climbing plant ({Periploca
      Gr[ae]ca}) of the Milkweed family, having a silky tuft on
      the seeds. It is native in Southern Europe.

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.

Source : WordNet®

Bombyx mori
     n : stocky creamy-white Asiatic moth found almost entirely under
         human care; the source of most of the silk of commerce
         [syn: {domestic silkworm moth}]