An agreement to buy or sell a particular commodity, currency or security for delivery at a fixed date in the future at a fixed price.

在将来某一缺定日期按约定价格购买或出售某项资产的协议。

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In an efficient market, such as that for shares or foreign exchange, such price rises would be moderated to some extent by other investors selling short (selling something for future delivery that they do not currently own, in the hope that they will be able to buy it more cheaply later).

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