mur·i·qui (mûr??-k??)n. pl. muriqui or mur·i·quis Either of two species of large arboreal leaf-eating monkeys (Brachyteles arachnoides or B. hypoxanthus) found only in Brazil, having a long prehensile tail and thick fleecy fur. Also called woolly spider monkey.[Portuguese buriqui, muriqui, from Tupí mbïrï?ki.]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.