Source : Webster's Revised Unabridged Dictionary (1913)

Spindle \Spin"dle\, n. [AS. spinal, fr. spinnan to spin; akin to
   D. spil, G. spille, spindel, OHG. spinnala. [root]170. See
   {Spin}.]
   1. The long, round, slender rod or pin in spinning wheels by
      which the thread is twisted, and on which, when twisted,
      it is wound; also, the pin on which the bobbin is held in
      a spinning machine, or in the shuttle of a loom.

   2. A slender rod or pin on which anything turns; an axis; as,
      the spindle of a vane. Specifically:
      (a) (Mach.) The shaft, mandrel, or arbor, in a machine
          tool, as a lathe or drilling machine, etc., which
          causes the work to revolve, or carries a tool or
          center, etc.
      (b) (Mach.) The vertical rod on which the runner of a
          grinding mill turns.
      (c) (Founding) A shaft or pipe on which a core of sand is
          formed.

   3. The fusee of a watch.

   4. A long and slender stalk resembling a spindle.

   5. A yarn measure containing, in cotton yarn, 15,120 yards;
      in linen yarn, 14,400 yards.

   6. (Geom.) A solid generated by the revolution of a curved
      line about its base or double ordinate or chord.

   7. (Zo["o]l.)
      (a) Any marine univalve shell of the genus {Rostellaria};
          -- called also {spindle stromb}.
      (b) Any marine gastropod of the genus {Fusus}.

   {Dead spindle} (Mach.), a spindle in a machine tool that does
      not revolve; the spindle of the tailstock of a lathe.

   {Live spindle} (Mach.), the revolving spindle of a machine
      tool; the spindle of the headstock of a turning lathe.

   {Spindle shell}. (Zo["o]l.) See {Spindle}, 7. above.

   {Spindle side}, the female side in descent; in the female
      line; opposed to {spear side}. --Ld. Lytton. [R.] ``King
      Lycaon, grandson, by the spindle side, of Oceanus.''
      --Lowell.

   {Spindle tree} (Bot.), any shrub or tree of the genus
      {Eunymus}. The wood of {E. Europ[ae]us} was used for
      spindles and skewers. See {Prickwood}.

Spindle \Spin"dle\, v. i. [imp. & p. p. {Spindled}; p. pr. & vb.
   n. {Spindling}.]
   To shoot or grow into a long, slender stalk or body; to
   become disproportionately tall and slender.

         It has begun to spindle into overintellectuality.
                                                  --Lowell.

Source : WordNet®

spindle
     n 1: (biology) tiny fibers that are seen in cell division; the
          fibers radiate from two poles and meet at the equator in
          the middle; "chromosomes are distributed by spindles in
          mitosis and meiosis"
     2: any of various rotating shafts that serve as axes for larger
        rotating parts [syn: {mandrel}, {mandril}, {arbor}]
     3: a stick or pin used to twist the yarn in spinning