Koo play biographical name \ˈkü\ Definition of Koo Vi Kyuin Wel*ling*ton play \ˈwe-liŋ-tən\ 1888–1985 originally Ku Wei-chün Chin. statesman & diplomat See words that rhyme with Koo Writing? Check your grammar now! Seen and Heard What made you want to look up Koo? Please tell us where you read or heard it (including the quote, if possible).