also knock-out
(~s)
1.
In boxing, a ~ is a situation in which a boxer wins the fight by making his opponent fall to the ground and be unable to stand up before the referee has counted to ten.
N-COUNT: also by N
2.
A ~ blow is an action or event that completely defeats an opponent.
He delivered a ~ blow to all of his rivals.
ADJ: ADJ n
3.
A ~ competition is one in which the players or teams that win continue playing until there is only one winner left. (mainly BRIT; in AM, use elimination )
...the European Cup, a ~ competition between the top teams in Europe.
ADJ: ADJ n
4.
If you describe someone or something as a ~, you think that they are extremely attractive or impressive. (INFORMAL)
She was a ~ in navy and scarlet...
N-SING: a N approval