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

pacemaker \pacemaker\ n. physiol.  anat.
   1. a specialized bit of heart tissue that controls the
      heartbeat.

   syn: cardiac pacemaker, sinoatrial node.
        wordnet 1.5

   2. an implanted electronic device that takes over the
      function of the natural cardiac pacemaker1; -- used to
      assist people whose heartbeat is irregular.

   syn: artificial pacemaker.
        wordnet 1.5

   3. a horse used to set the pace in racing.

   syn: pacer, pacesetter.
        wordnet 1.5

[2] : WordNet (r) 2.0

pacemaker
     n 1: a leading instance in its field; "the new policy will be a
          pacesetter in community relations" syn: pacesetter
     2: a specialized bit of heart tissue that controls the
        heartbeat syn: cardiac pacemaker, sinoatrial node, sa
        node
     3: an implanted electronic device that takes over the function
        of the natural cardiac pacemaker syn: artificial
        pacemaker
     4: a horse used to set the pace in racing syn: pacer, pacesetter
see also:
pacesetter cardiac pacemaker sinoatrial node sa node artificial pacemaker pacer 

Pacemaker >> P Words
Pacemaker, definition of term: Pacemaker
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