KAYO BOXING, Meaning of KAYO BOXING, in English [ keɪ'əʊ ]informal■ noun ( plural kayos ) a knockout. ■ verb ( kayoes , kayoing , kayoed ) knock (someone) out.Origin1920s: representing the pronunciation of KO . Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004