Ucayali 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 E Peru, flowing north to join the Marañón & form the Amazon: c. 1,200 mi (1,931 km)
Ucayali definition by American Heritage Dictionary
A river of eastern Peru flowing about 1,609 km (1,000 mi) northward to join the Marañón River and form the Amazon River.