Eastern Roman Empire

noun
1.
the eastern part of the Roman Empire, especially after the division in a.d. 395, having its capital at Constantinople: survived the fall of the Western Roman Empire in a.d. 476.
Also called Eastern Empire.
Compare Byzantine Empire.
British Dictionary definitions for Eastern Roman Empire

Eastern Roman Empire

noun
1.
the eastern of the two empires created by the division of the Roman Empire in 395 ad See also Byzantine Empire