Hedge
A hedge is a protective position against an open trade. You do not close the main position. You open a second one that moves the opposite way. A loss on one is partly offset by profit on the other.
The catch is that a hedge also cuts your possible profit, and every extra position adds spread and commissions. Some brokers do not allow an opposite position on the same pair at all.
Example
You are long EUR/USD, and big news lands in an hour. You do not want to close the trade, so you open an equal short. While it stays open, the result barely moves. After the news you close the hedge.
What not to do
Do not keep a hedge "just in case" for weeks. You pay for both positions and earn nothing. Decide in advance when you will close the hedge or the main trade.
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