Source : Webster's Revised Unabridged Dictionary (1913)

Stakeholder \Stake"hold`er\, n.
   The holder of a stake; one with whom the bets are deposited
   when a wager is laid.

Source : WordNet®

stakeholder
     n : someone entrusted to hold the stakes for two or more persons
         betting against one another; must deliver the stakes to
         the winner