Donets Syllabification: (Do·nets)Pronunciation: /dəˈn(y)ets/Definition of Donets a river in eastern Europe that rises near Belgorod in southern Russia and flows southeast for about 630 miles (1,000 km) through Ukraine before re-entering Russia and joining the Don River near Rostov. Donets in other Oxford dictionaries Definition of Donets in the British & World English dictionary