working or done secretly in order to find out information for the police, a government, etc. 秘密工作的;暗中做的;私下进行的 an undercover agent 密探 an undercover operation/investigation 秘密行动/调查 The scandal was revealed after months of undercover work by journalists. 经过新闻记者数个月的暗中调查,丑闻被揭露出来。
Oxford Collocations DictionaryUndercover is used with these nouns:- agent
- detective
- mission
- …