proxy

 
Pronunciation: /ˈprɒksi/

noun (plural proxies)

  • 1 [mass noun] the authority to represent someone else, especially in voting: Britons overseas may register to vote by proxy
  • [count noun] a person authorized to act on behalf of another.
  • [count noun] a document authorizing a person to vote on another’s behalf.
  • 2a figure that can be used to represent the value of something in a calculation: the use of a US wealth measure as a proxy for the true worldwide measure

Origin:

late Middle English: contraction of procuracy