Derivative instruments: a contract whose value changes as prices move in a related or underlying commodity or financial instrument.

衍生金融工具：一种合同，其价值随着有关或特定商品或金融工具的价格变动而变化。

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Derivatives instruments are derived from underlying cash assets that can be bought, sold and traded in a similar way to shares or any other financial instrument.

金融衍生工具由现货市场的标的资产(underlying cash assets)衍生出来，标的资产的交易方式如同股票或其他金融工具。

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Derivatives are financial instruments whose value is based on some underlying asset, like a mortgage for instance, and and can be used to either hedge risk or for completely speculative positions.

FORBES: Another Financial Crisis Is On The Way, Mobius Says

These instruments are called 'derivatives' because they derive from an underlying financial asset - in this case, share prices.

BBC: Hedging - a rough guide