The Collaborative International Dictionary of English v.0.48:

Proxy \Prox"y\, n.; pl. Proxies. [Contr. from procuracy. Cf.
   Proctor.]
   1. The agency for another who acts through the agent;
      authority to act for another, esp. to vote in a
      legislative or corporate capacity.
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            I have no man's proxy: I speak only for myself.
                                                  --Burke.
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   2. The person who is substituted or deputed to act or vote
      for another.
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            Every peer . . . may make another lord of parliament
            his proxy, to vote for him in his absence.
                                                  --Blackstone.
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   3. A writing by which one person authorizes another to vote
      in his stead, as in a corporation meeting.
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   4. (Eng. Law) The written appointment of a proctor in suits
      in the ecclesiastical courts. --Burrill.
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   5. (Eccl.) See Procuration. [Obs.]
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