Gi·ku·yu (g?-ko?o?yo?o)n. Variant of Kikuyu.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.Ki?ku?yu (k??ku yu) n., pl. -yus, (esp. collectively) -yu. 1. a member of an African people or group of peoples mainly of the E and S of Mount Kenya in S central Kenya. 2. the Bantu language of the Kikuyu. Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.