The Collaborative International Dictionary of English v.0.48:

Ruddock \Rud"dock\, n. [AS. ruddic; cf. W. rhuddog the
   redbreast. [root]113. See Rud, n.] [Written also
   raddock.]
   1. (Zool.) The European robin. "The tame ruddock and the
      coward kite." --Chaucer.
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   2. A piece of gold money; -- probably because the gold of
      coins was often reddened by copper alloy. Called also red
      ruddock, and golden ruddock. [Obs.]
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            Great pieces of gold . . . red ruddocks. --Florio.
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