knockout Definition

1. colloq
Someone or something stunning
Example: Brad Pitt is such a knockout!
Thesaurus: success, sensation, triumph, hit, smash, winner.
2. A competition in which the defeated teams or competitors are dropped after each round.
3a. boxing.
The act of rendering someone unconscious;
3b. boxing.
A blow that renders the opponent or victim unconscious.
Thesaurus: knockout blow, coup de grace, finishing blow, final blow, technical knockout, KO, TKO.

1. Said of a competition: in which the losers in each round are eliminated.
2. Said of a punch, etc: leaving the victim unconscious.
3. colloq
Stunningly attractive; excellent.