Eccentric \Ec*cen"tric\ ([e^]k*s[e^]n"tr[i^]k), a. [F.
   excentrique, formerly also spelled eccentrique, fr. LL.
   eccentros out of the center, eccentric, Gr. 'e`kkentros; 'ek
   out of + ke`ntron center. See {Ex-}, and {Center}, and cf.
   {Excentral}.]
   1. Deviating or departing from the center, or from the line
      of a circle; as, an eccentric or elliptical orbit;
      pertaining to deviation from the center or from true
      circular motion.
      
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   2. Not having the same center; -- said of circles, ellipses,
      spheres, etc., which, though coinciding, either in whole
      or in part, as to area or volume, have not the same
      center; -- opposed to {concentric}.
      
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   3. (Mach.) Pertaining to an eccentric; as, the eccentric rod
      in a steam engine.
      
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   4. Not coincident as to motive or end.
      
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            His own ends, which must needs be often eccentric to
            those of his master.                  --Bacon.
      
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   5. Deviating from stated methods, usual practice, or
      established forms or laws; deviating from an appointed
      sphere or way; departing from the usual course; irregular;
      anomalous; odd; as, eccentric conduct. "This brave and
      eccentric young man." --Macaulay.
      
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            He shines eccentric, like a comet's blaze. --Savage.
      
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   {Eccentric anomaly}. (Astron.) See {Anomaly}.

   {Eccentric chuck} (Mach.), a lathe chuck so constructed that
      the work held by it may be altered as to its center of
      motion, so as to produce combinations of eccentric
      combinations of eccentric circles.

   {Eccentric gear}. (Mach.)
      (a) The whole apparatus, strap, and other parts, by which
          the motion of an eccentric is transmitted, as in the
          steam engine.
      (b) A cogwheel set to turn about an eccentric axis used to
          give variable rotation.

   {Eccentric hook} or {Eccentric gab}, a hook-shaped journal
      box on the end of an eccentric rod, opposite the strap.

   {Eccentric rod}, the rod that connects an eccentric strap
      with any part to be acted upon by the eccentric.

   {Eccentric sheave}, or {Eccentric pulley}, an eccentric.

   {Eccentric strap}, the ring, operating as a journal box, that
      encircles and receives motion from an eccentric; -- called
      also {eccentric hoop}.

   Syn: Irregular; anomalous; singular; odd; peculiar; erratic;
        idiosyncratic; strange; whimsical.
        
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Eccentric \Ec*cen"tric\ ([e^]k*s[e^]n"tr[i^]k), n.
   1. A circle not having the same center as another contained
      in some measure within the first.
      
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   2. One who, or that which, deviates from regularity; an
      anomalous or irregular person or thing.
      
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   3. (Astron.)
      (a) In the Ptolemaic system, the supposed circular orbit
          of a planet about the earth, but with the earth not in
          its center.
      (b) A circle described about the center of an elliptical
          orbit, with half the major axis for radius. --Hutton.
          
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   4. (Mach.) A disk or wheel so arranged upon a shaft that the
      center of the wheel and that of the shaft do not coincide.
      It is used for operating valves in steam engines, and for
      other purposes. The motion derived is precisely that of a
      crank having the same throw.
      
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   {Back eccentric}, the eccentric that reverses or backs the
      valve gear and the engine.

   {Fore eccentric}, the eccentric that imparts a forward motion
      to the valve gear and the engine.
      
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