A howler monkey in a tree.
howler monkey 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.
any of a genus (Alouatta, family Cebidae) of large New World monkeys with a loud, howling cry and a long, prehensile tail
occasionally called howling monkey
howler monkey definition by American Heritage Dictionary
Any of several monkeys of the genus Alouatta of tropical America, having a long prehensile tail and an extremely loud, howling call.