An established rule, principle, or law.

尤其由先例形成的法律的原理、规则。

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The stronger one must drive out the Devil with Beelzebub, as the saying goes, to present a dose of counter-magic in order to neutralize and overcome that which supports established rule.

较强的工具必须以恶魔驱除恶魔，如同谚语所说，为了呈现一剂对抗魔力，才能中立并克服支持既有规则的魔力。

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He established one-man rule in his country seven months ago.

他七个月前在自己的国家建立了个人统治。

《柯林斯英汉双解大词典》

The doctrine is a long-established rule which allows the reselling of goods to a new owner.

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An established rule holds that a country cannot successfully fix both its interest rate and its exchange rate especially as its economy becomes more open.

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They have also taken an even bolder step - rejecting a long-established rule of Muslim scholars that later (and often more conservative) texts override earlier ones.

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