Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
common denominator n (MATH) о́бщий*знамена́тель m (characteristic) о́бщая черта́; (attitude) о́бщее*мне́ние
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.
Русский: