Belorussian Syllabification: (Be·lo·rus·sian)Pronunciation: /ˌbelōˈrəSHən/ (also Byelorussian /ˌbyelō-/)Definition of Belorussian adjective of or relating to Belarus, its people, or its language. noun 1a native or inhabitant of Belarus. a person of Belorussian descent. 2the East Slavic language of Belarus. Belorussian in other Oxford dictionaries Definition of Belorussian in the British & World English dictionary