counterintelligence
From Longman Dictionary of Contemporary EnglishRelated topics: Government, Militarycounterintelligencecoun‧ter‧in‧tel‧li‧gence /ˌkaʊntərɪnˈtelədʒəns/ noun [uncountable] PGPMaction that a country takes in order to stop other countries discovering its secretsExamples from the Corpuscounterintelligence• If counterintelligence becomes the overriding mission, the obvious answer is the solution first offered by Sen.