(especially British English)a knockout competition is one in which the winning player/team at each stage competes in the next stage and the losing one no longer takes part in the competition淘汰赛的;淘汰的
the knockout stages of the tournament锦标赛的淘汰赛阶段
a knockout blow is something that hits somebody so hard that they can no longer get up击败对手的
The cancellation of the flight delivered the knockout blow to his plans.航班的取消给他的计划带来了打击。