utajni|ć

pf — utajni|ać impf vt książk. to treat [sth] as classified (information)

- utajnić fakty historyczne to treat historical facts as classified (information)

- utajnić raport/wyniki sondaży/obrady komisji/śledztwo to keep the report/poll results/committee proceedings/investigation secret

- utajnione dokumenty classified documents