knock·out
ˈnäk-ˌau̇t 
1
a
: the act of knocking out : the condition of being knocked out
b(1)
: the termination of a boxing match when one boxer has been knocked down and is unable to rise and resume boxing within a specified time
(2)
c
: a blow that knocks out an opponent
2
: a sensationally striking, appealing, or attractive person or thing
1
: causing a knockout
a knockout blow
2
: sensationally striking, appealing, or attractive
a knockout dress
3
: having all or part of a gene eliminated or inactivated by genetic engineering
knockout mice predisposed to diabetes mellitus
knocked out; knocking out; knocks out
1
: to produce roughly or hastily
2
a(1)
: to defeat (a boxing opponent) by a knockout
(2)
: to make unconscious
the drug knocked him out
b
: to make inoperative or useless
electricity was knocked out by the storm
c
: to get rid of : eliminate
knocked out illegal gambling
3
: to tire out : exhaust
knocked themselves out with work
4
: to cause (an opposing pitcher) to be removed from a baseball game by a batting rally
Synonyms
Noun
- babe [slang]
- beauty
- beauty queen
- cookie
- cooky
- cutie
- cutey
- dolly bird [British]
- enchantress
- eyeful
- fox
- goddess
- honey
- queen
- stunner
Adjective
- aesthetic
- esthetic
- aesthetical
- esthetical
- attractive
- beauteous
- beautiful
- bonny [chiefly British]
- bonnie
- comely
- cute
- drop-dead
- fair
- fetching
- good
- good-looking
- goodly
- gorgeous
- handsome
- likely
- lovely
- lovesome
- pretty
- ravishing
- seemly
- sightly
- stunning
- taking
- well-favored
Verb
Examples of knockout in a Sentence
Noun
He won the match by a knockout.
He scored a knockout in the fourth round.
She's a real knockout in that dress.
Adjective
The Wimbledon tennis tournament is a knockout competition.
a knockout sports car that's the talk of the neighborhood
Verb
the entire staff knocked itself out getting the project finished on time
Recent Examples on the Web
Sam Joseph, CNN, 27 June 2024
Drawn into a group with Jamaica, Ecuador and Venezuela, none of which are ranked inside the top 30 in the world, the bare minimum — the minimum — Mexico had to achieve in the tournament was to finish in the top two and advance to the knockout stages.
—Kevin Baxter, Los Angeles Times, 27 June 2024
Leo Schwartz, Fortune Crypto, 3 Feb. 2023
Addison Rae added to the ever-growing list of knockout vintage Y2K, donning a wrap skirt from Roberto Cavalli’s spring 2000 collection.
—André-Naquian Wheeler, Vogue, 28 Jan. 2023
Frank Witsil, Detroit Free Press, 17 June 2024
In a New York Times column this week, Goodell focused on last month’s windstorm in Houston that knocked out power for nearly a million customers.
—Michael Smolens, San Diego Union-Tribune, 7 June 2024
See all Example Sentences for knockout 
Noun
This means that 16 clubs will play a minimum of 10 matches Champions League matches per season, all before even advancing to the knockout stage.
—Sam Joseph, CNN, 27 June 2024
Drawn into a group with Jamaica, Ecuador and Venezuela, none of which are ranked inside the top 30 in the world, the bare minimum — the minimum — Mexico had to achieve in the tournament was to finish in the top two and advance to the knockout stages.
—Kevin Baxter, Los Angeles Times, 27 June 2024
Adjective
The knockout blow to the fighter, as Findeisen gleefully pointed out, was the name of the fake NFT project, SourzNFT Candies are Moundbound.
—Leo Schwartz, Fortune Crypto, 3 Feb. 2023
Addison Rae added to the ever-growing list of knockout vintage Y2K, donning a wrap skirt from Roberto Cavalli’s spring 2000 collection.
—André-Naquian Wheeler, Vogue, 28 Jan. 2023
Verb
More:Deadly tornado in Livonia struck without warning The weather also knocked out power to thousands of customers.
—Frank Witsil, Detroit Free Press, 17 June 2024
In a New York Times column this week, Goodell focused on last month’s windstorm in Houston that knocked out power for nearly a million customers.
—Michael Smolens, San Diego Union-Tribune, 7 June 2024
See all Example Sentences for knockout
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'knockout.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Dictionary Entries Near knockout
Cite this Entry
“Knockout.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/knockout. Accessed 2 Jul. 2024.
Copy CitationKids Definition
knockout
1 of 2 noun
knock·out
ˈnäk-ˌau̇t
1
: the act of knocking out : the condition of being knocked out
2
: something or someone very striking or attractive
knockout
adjective
knock out
2 of 2 verbˈnäk-ˈau̇t,
näk-ˈau̇t
: to make unconscious
Medical Definition
knockout
adjective
knock·out
ˈnäk-ˌau̇t
: having all or part of a gene eliminated or inactivated by genetic engineering
knockout mice predisposed to diabetes mellitus serve as animal models in the study of human diabetes
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