undercover work

English Thesaurus

1. the act of keeping a secret watch for intelligence purposes (noun.act)

hypernym	:	intelligence, intelligence activity, intelligence operation,
definition	:	the operation of gathering information about an enemy (noun.act)

hyponym	:	espionage,
definition	:	the systematic use of spies to get military or political secrets (noun.act)

derivation	:	spy,
definition	:	secretly collect sensitive or classified information; engage in espionage (verb.communication)

derivation	:	spy,
definition	:	secretly collect sensitive or classified information; engage in espionage (verb.communication)