ENGLISH
REFERENCE

knockout

n. · adj.
US //ˈnɑˌkaʊt// UK //nˈɒkaʊt// knock·out
  1. 1 combat sports (n.)
    B1 Intermediate Sport

    a hit that makes a fighter unconscious or unable to continue the fight.

    the act of rendering an opponent unconscious or unable to resume a contest within a specified time limit.

    Example

    The champion won the match with a powerful knockout in the third round.

    Example

    The referee stopped the bout immediately after the knockout, ensuring the medical team could attend to the fallen fighter without delay.
  2. 2 elimination tournament (n.)
    B2 Upper Intermediate Sport

    a competition where a player or team is removed after losing one game.

    a tournament format in which the loser of each match is immediately eliminated from the competition.

    Example

    Our local team was eliminated in the first round of the knockout.

    Example

    The knockout stages of the tournament often produce more dramatic results because there is no margin for error in a single-elimination format.
    • round robin
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  1. 3 attractive person (n.)
    B2 Upper Intermediate Informal

    someone who is extremely attractive or beautiful.

    an exceptionally attractive or impressive person, often used to describe a woman.

    Example

    Everyone turned to look when she walked in; she was a total knockout.

    Example

    The lead actress was a complete knockout, though critics argued that her performance lacked the depth required for such a complex role.
  2. 4 genetics (n.)
    C2 Proficiency Technical Science

    the process of turning off a specific gene in a living thing for science.

    the genetic engineering technique of deactivating a specific gene to observe the resulting phenotypic changes.

    Example

    The scientists used a gene knockout to study how the heart develops.

    Example

    By creating a knockout mouse, the researchers were able to demonstrate that the specific protein was essential for long-term memory formation.
  3. 5 impressive or beautiful (adj.)
    B2 Upper Intermediate Informal

    extremely impressive, beautiful, or successful.

    strikingly attractive or impressive; having a powerful effect.

    Example

    She wore a knockout dress to the awards ceremony.

    Example

    The marketing team delivered a knockout presentation that secured the contract despite stiff competition from larger agencies.
Origin

Deverbal from knock out.

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