Russian (n.)youdaoicibaDictYouDict[Russian 词源字典]
1530s, from Medieval Latin Russianus, from Russia (see Russia). Slang or colloquial Russki "Russian" (1858) is from Russian Russkiy. Russian roulette attested from 1937. Russian dressing for salads is from 1915.[Russian etymology, Russian origin, 英语词源]