It has the functions of preestablishing secret code, keeping secret well, error code warning and less power consumption, etc.

该密码锁具有密码预置，保密性强，误码报警，耗电极省等特点。

youdao

You answered that you majored in course 2. It sounds like a secret code to outsiders.

你刚才回答你的专业是课程2。这在外人听起来就像是秘密代码一样。

MIT用数字说话 - SpeakingMax英语口语达人

or whatever. Like, you know, you're speaking the secret code,

好像你在说密码一样，

社团小组信息 - SpeakingMax英语口语达人

The passwords themselves were encrypted, meaning they couldn't be read without breaking the secret code that protected them.

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"It's a miniature kinetic sculpture" that conveys "a secret code" to other wearers.

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What began is a secret code word between stoners has gone mainstream.

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