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English definition of “undercover”


adjective [before noun]     /ˌʌn.dəˈkʌv.ər/ US  /-dɚˈkʌv.ɚ/
working secretly using a false appearance in order to get information for the police or government: an undercover police operation an undercover detectiveHiding and disguisingThe police generally undercover     adverb He was working undercover at the time, almost certainly for the British Secret Service.Hiding and disguisingThe police generally
(Definition of undercover adjective from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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