# knock out

CEFR B1 · Phrasal verb

Source: https://englishreference.com/word/knock-out
Updated: 2026-10-22

## Definition

to hit someone so hard that they fall down and become unconscious for a short time. You also use this when a team loses a game and has to leave a competition.

For teachers: to render a person unconscious, typically through a physical blow; by extension, to eliminate a competitor from a tournament. The verb is transitive and frequently appears in the passive voice.

## Examples

- A strong punch often knocks out an opponent in boxing.
- The star player was accidentally knocked out during the match after a heavy collision with the defender, requiring immediate medical attention on the field.
- Despite their early dominance, the defending champions were knocked out of the tournament following a series of tactical errors and a lack of clinical finishing in the final minutes.

## Pitfalls

- Not "The punch knocked out him." but "The punch knocked him out." — When the object is a pronoun, it must be placed between the verb and the particle.

## Usage notes

- This verb is separable, meaning the object can sit between 'knock' and 'out'.
- Teaching tip: Distinguish between the physical act of causing unconsciousness and the metaphorical sense of elimination in sports to help students navigate different contexts.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.