Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
secretive [ˈsiːkrətɪv] adj (pej)(person) скры́тный*скры́тен
he is secretive about his plans он де́ржит свои́ пла́ны в секре́те
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.
Русский: