The Collaborative International Dictionary of English v.0.48:

partaker \par*tak"er\ (p[aum]r*t[=a]k"[~e]r), n.
   1. One who partakes; a sharer; a participator.
      [1913 Webster]

            Partakers of their spiritual things.  --Rom. xv. 27.
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            Wish me partaker in my happiness.     --Shark.
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   2. An accomplice; an associate; a partner. [Obs.]
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            Partakers wish them in the blood of the prophets.
                                                  --Matt. xxiii.
                                                  30.
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WordNet (r) 3.0 (2006):

partaker
    n 1: someone who has or gives or receives a part or a share
         [syn: partaker, sharer]