rocker arm

rocker arm
    n 1: a lever pivoted at the center; used especially to push a
         valve down in an internal-combustion engine [syn: {rocker
         arm}, {valve rocker}]
    

Rocker \Rock"er\, n.
   1. One who rocks; specifically, one who rocks a cradle.
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            It was I, sir, said the rocker, who had the honor,
            some thirty years since, to attend on your highness
            in your infancy.                      --Fuller.
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   2. One of the curving pieces of wood or metal on which a
      cradle, chair, etc., rocks.
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   3. Any implement or machine working with a rocking motion, as
      a trough mounted on rockers for separating gold dust from
      gravel, etc., by agitation in water.
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   4. A play horse on rockers; a rocking-horse.
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   5. A chair mounted on rockers; a rocking-chair.
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   6. A skate with a curved blade, somewhat resembling in shape
      the rocker of a cradle.
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   7. (Mach.) Same as {Rock shaft}.
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   {Rocker arm} (Mach.), an arm borne by a rock shaft.
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