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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.
Compare Byzantine Empire.
Also called Eastern Empire.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for eastern empire

Eastern Roman Empire

noun
  1. the eastern of the two empires created by the division of the Roman Empire in 395 adSee also Byzantine Empire
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012