Definition from Wiktionary, the free dictionary
Related to Ruthene, Ruthenian, from Medieval Latin Rutheni, Ruteni, related to Russi, Ruzi as Prutheni, Pruteni is to Prussi, Pruzi (“Prussians”). Cf. Rus, Russ, from Old East Slavic Русь (Rus’), compare medieval Greek οί Ῥῶς (oi Rhos).
Proper noun 
- The territory of Eastern Europe inhabited by Rusyns, on the slopes of the Carpathian Mountains in parts of Ukraine, Poland and Slovakia.
- (historical) Lands inhabited by Ukrainians (Ruthenians) of the former Austrian Empire kingdom of Galicia (1772–1918), corresponding to parts of Western Ukraine.
- (historical) Western East-Slavic lands, including the principalities of Halych-Volynia and Kiev, which united with Lithuania and Poland (14th c–1772), corresponding to parts of Belarus and Ukraine.
- (historical) Rus, an East Slavic medieval state (880–12th c), corresponding to parts of Belarus, Russia, and Ukraine.
- Russia (Latin)
- Carpathian Ruthenia, Transcarpathia, Subcarpathian Rus
- Red Ruthenia (Červona Rus’)
- Kievan Rus, Kievan Russia
Related terms 
- OED (Ruthenian, Ruthene, Russniak)