1、knock out的意思是：敲空；击倒；打破；使筋疲力竭。2、knock out的英英释义是Verb:eliminate;"knock out a target"knock unconscious or senseless;"the boxing champion knocked out his opponent in a few seconds"destroy or break forcefully;"The windows were knocked out"overwhelm with admiration;"All the guys were knocked out by her charm"empty (as of tobacco) by knocking out;"knocked out a pipe"。3、knock out的读音是英[nɒkaʊt]；美[nɑːkaʊt]。