Rondônia (Portuguese ro??donja) n (Placename) a state of W Brazil: consists chiefly of tropical rainforest; a centre of the Amazon rubber boom until about 1912. Capital: Porto Velho. Pop: 1 431 777 (2002). Area: 243 043 sq km (93 839 sq miles). Former name (until 1956): Guaporé Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014Ron?dô?nia (r?n?do?n y?, ro???-) n. a state in W Brazil. 1,221,290; 93,815 sq. mi. (242,980 sq. km). Cap.: Pôrto Velho. Formerly, Guaporé. Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.