(plural proxies)

1the act or practice of a person serving as an authorized agent or substitute for another used especially in the phrase by    proxy
2  a authority or power to act for another
   b a statement or document giving such authorization; specifically an oral consent or written document (as a power of attorney) given by a stockholder to a specified person or persons to vote corporate stock

3   a a person authorized to act or make decisions for another 

  • appointed a health-care proxy  
  • b something serving to replace or substitute for another thing