Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
second-class [ˈsɛkəndˈklɑːs] adj (citizen, standard etc) второразря́дный; (POST, RAIL) второ́го кла́сса
adv вторы́м кла́ссом
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.
Русский: