Cai·ro (k??r?) The capital and largest city of Egypt, in the northeast part of the country on the Nile River. Old Cairo was built c. 642 as a military camp; the new city was founded c. 968 by the Fatimid dynasty and reached its greatest prosperity under the Mameluke sultans (13th-16th century).American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.Cairo (?ka?r??) n (Placename) the capital of Egypt, on the Nile: the largest city in Africa and in the Middle East; industrial centre; site of the university and mosque of Al Azhar (founded in 972). Pop: 11 146 000 (2005 est). Arabic name: El Qahira ?Cairene n, adjCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014Cai?ro (?ka? ro?) n. the capital of Egypt, in the N part on the E bank of the Nile. 6,325,000. Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.