state secret

基本解释

In private even academics in favour of hydropower development complain that nearly all relevant information, even the amount of rain that reaches them, is treated as a state secret.
私下，甚至一些支持水利事业发展的学者抱怨，他们得到的所有相关信息，甚至包括降雨量，都被视为国家机密。
Because the minister was also a close friend of M. Walter, it was not difficult for de Cantel's new paramour to learn the state secret that France would soon guarantee the Moroccan debt.
因为部长也是华代尔先生的密友，所以德•坎特尔的新情人不费什么周折便了解到一项国家机密：法国不久将承诺担保摩洛哥的债务。
The exact number is a state secret.
准确的数字属于国家秘密。

He's recovering from intestinal surgery and an undisclosed illness that's treated as a state secret.
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The Supreme Court accepted the idea of a state secret privilege more than 50 years ago.
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Grain reserves are said to be at a record high—although their precise level remains a state secret.
ECONOMIST: China