KO Meaning of KO in English KO, k.o. BrE AmE ˌkeɪ ˈəʊ AmE \ -ˈoʊ▷ KO|'d d▷ KO|'ing ɪŋ▷ KO|'s z Longman Pronunciation English Dictionary. Английский словарь произношений Longman. 2012