Tailstock

from WordNet (r) 3.0 (2006)

tailstock
    n 1: support consisting of the movable part of a lathe that
         slides along the bed in alignment with the headstock and is
         locked into position to support the free end of the
         workpiece

from The Collaborative International Dictionary of English v.0.48

Tailstock \Tail"stock`\, n.
   The sliding block or support, in a lathe, which carries the
   dead spindle, or adjustable center. The {headstock} supports
   the live spindle.
   [1913 Webster]

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