This is the 11771st most frequent Polish word.
kontrwywiadu
Counterintelligence.
'Kontrwywiadu' is used here in the possessive case (genitive) to denote activities related to the institution.
Działania kontrwywiadu są kluczowe dla ochrony kraju.
The actions of counterintelligence are crucial for the country's security.
'Kontrwywiadu' is used as a noun in the genitive case to describe the employee's affiliation.
Pracownik kontrwywiadu często działa w tajemnicy.
A counterintelligence employee often works in secrecy.
'Kontrwywiadu' is again in the genitive case, modifying its relationship to effectiveness.