Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
unfit [ʌnˈfɪt] adj (physically)
she is unfit она́ в плохо́й спорти́вной фо́рме
he is unfit for the job он неприго́ден к рабо́те
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.