Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
operative [ˈɔpərətɪv] adj (law etc) де́йствующий#; (position) операти́вный
n (in factory) опера́тор
the operative word ключево́е сло́во#
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.
Русский: