law: Indian Contract Act, 1872 
  31. "Contingent contract"
  
  defined 
  A "contingent contract" is a contract to do or not to
  
  do something, if some event, collateral to such contract, does or does not
  
  happen.
   Illustration 
  A contracts to pay to B Rs. 10,000 if B's house is burnt. This
  
  is a contingent contract.