Source : Webster's Revised Unabridged Dictionary (1913)

Bobbin \Bob"bin\, n. [F. bobine; of uncertain origin; cf. L.
   bombus a humming, from the noise it makes, or Ir. & Gael.
   baban tassel, or E. bob.]
   1. A small pin, or cylinder, formerly of bone, now most
      commonly of wood, used in the making of pillow lace. Each
      thread is wound on a separate bobbin which hangs down
      holding the thread at a slight tension.

   2. A spool or reel of various material and construction, with
      a head at one or both ends, and sometimes with a hole
      bored through its length by which it may be placed on a
      spindle or pivot. It is used to hold yarn or thread, as in
      spinning or warping machines, looms, sewing machines, etc.

   3. The little rounded piece of wood, at the end of a latch
      string, which is pulled to raise the latch.

   4. (Haberdashery) A fine cord or narrow braid.

   5. (Elec.) A cylindrical or spool-shaped coil or insulated
      wire, usually containing a core of soft iron which becomes
      magnetic when the wire is traversed by an electrical
      current.

   {Bobbin and fly frame}, a roving machine.

   {Bobbin lace}, lace made on a pillow with bobbins; pillow
      lace.

Source : WordNet®

bobbin
     n : a winder around which thread or tape or film or other
         flexible materials can be wound [syn: {spool}, {reel}]