1, The purchase or sale of a futures contract as a temporary substitute for a cash market transaction to be made at a later date. Usually it involves opposite positions in the cash market and futures market at the same time.
2, The practice of offsetting the price risk inherent in any cash market position by taking an equal but opposite position in the futures market. Hedgers use the futures markets to protect their businesses from adverse price changes. (See Selling (Short) Hedge and Purchasing (Long) Hedge.)
3, The practice of undertaking one investment activity in order to protect against loss in another, e.g. selling short to nullify a previous purchase, or buying long to offset a previous short sale. While hedges reduce potential losses, they also tend to reduce potential profits.