double agent

(为敌对双方服务的)双重间谍

例句与用法：

Double agents live in a perpetual state of fear.

两面派永远过着提心吊胆的生活。

A spy who operates from within an organization, especially a double agent operating against his or her own government from within its intelligence establishment.

间谍一个间谍，活动于一个组织内部，尤指一个双重间谍，从其情报建立的机构内部从事反对他的或她的政府的活动

详细释义：

ph.

双重间谍