YAH-BOO Meaning of YAH-BOO in English Yah-boo /ˌjɑː ˈbuː/ BrE AmE ( also ˌyah-boo ˈsucks ) interjection British English used to express dislike or disrespect for someone, or to make fun of them Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012