The Collaborative International Dictionary of English v.0.48:

Thimble \Thim"ble\, n. [OE. thimbil, AS. ??mel, fr. ??ma a
   thumb. [root]56. See Thumb.]
   1. A kind of cap or cover, or sometimes a broad ring, for the
      end of the finger, used in sewing to protect the finger
      when pushing the needle through the material. It is
      usually made of metal, and has upon the outer surface
      numerous small pits to catch the head of the needle.
      [1913 Webster]

   2. (Mech.) Any thimble-shaped appendage or fixure.
      Specifically:
      (a) A tubular piece, generally a strut, through which a
          bolt or pin passes.
      (b) A fixed or movable ring, tube, or lining placed in a
          hole.
      (c) A tubular cone for expanding a flue; -- called
          ferrule in England.
          [1913 Webster]

   3. (Naut.) A ring of thin metal formed with a grooved
      circumference so as to fit within an eye-spice, or the
      like, and protect it from chafing.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Bushing \Bush"ing\, n. [See 4th Bush.]
   1. The operation of fitting bushes, or linings, into holes or
      places where wear is to be received, or friction
      diminished, as pivot holes, etc.
      [1913 Webster]

   2. (Mech.) A bush or lining; -- sometimes called a thimble.
      See 4th Bush.
      [1913 Webster]

WordNet (r) 3.0 (2006):

thimble
    n 1: as much as a thimble will hold [syn: thimble,
         thimbleful]
    2: a small metal cap to protect the finger while sewing; can be
       used as a small container