Beni definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
river in NW Bolivia, rising in the Andes, flowing northward to join the Mamoré and form the Madeira: c. 1,000 mi (1,609 km)
Beni definition by American Heritage Dictionary
A river of central and northwest Bolivia rising in the Andes and flowing about 1,599 km (994 mi) to the Mamoré River.