[1] : The Collaborative International Dictionary of English v.0.48

headstock \head"stock`\ -sto^k`, n. mach.
   a part usually separate from the bed or frame for
   supporting some of the principal working parts of a machine;
   as:
   a the part of a lathe that holds the revolving spindle and
       its attachments; -- also called poppet head, the
       opposite corresponding part being called a tailstock.
   b the part of a planing machine that supports the cutter,
       etc.
       1913 webster
see also:
poppet head 

[2] : WordNet (r) 2.0

headstock
     n : the stationary support in a machine or power tool that
         supports and drives a revolving part as a chuck or the
         spindle on a lathe

Headstock >> H Words
Headstock, definition of term: Headstock
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