Shuttle shell

Shuttle \Shut"tle\, n. [Also shittle, OE. schitel, scytyl,
   schetyl; cf. OE. schitel a bolt of a door, AS. scyttes; all
   from AS. sce['o]tan to shoot; akin to Dan. skyttel, skytte,
   shuttle, dial. Sw. skyttel, sk["o]ttel. [root]159. See
   {Shoot}, and cf. {Shittle}, {Skittles}.]
   1. An instrument used in weaving for passing or shooting the
      thread of the woof from one side of the cloth to the other
      between the threads of the warp.
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            Like shuttles through the loom, so swiftly glide
            My feathered hours.                   --Sandys.
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   2. The sliding thread holder in a sewing machine, which
      carries the lower thread through a loop of the upper
      thread, to make a lock stitch.
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   3. A shutter, as for a channel for molten metal. [R.]
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   {Shuttle box} (Weaving), a case at the end of a shuttle race,
      to receive the shuttle after it has passed the thread of
      the warp; also, one of a set of compartments containing
      shuttles with different colored threads, which are passed
      back and forth in a certain order, according to the
      pattern of the cloth woven.

   {Shutten race}, a sort of shelf in a loom, beneath the warp,
      along which the shuttle passes; a channel or guide along
      which the shuttle passes in a sewing machine.

   {Shuttle shell} (Zool.), any one of numerous species of
      marine gastropods of the genus {Volva}, or {Radius},
      having a smooth, spindle-shaped shell prolonged into a
      channel at each end.
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