\ ˈnäk How to pronounce knock (audio) \
knocked; knocking; knocks

Definition of knock

 (Entry 1 of 2)

intransitive verb

1 : to strike something with a sharp blow
2 : to collide with something
3a : bustle heard them knocking around in the kitchen
b : wander knocked about Europe all summer
4a : to make a pounding noise
b : to have engine knock
5 : to find fault

transitive verb

1a(1) : to strike sharply
(2) : to drive, force, or make by or as if by so striking was knocked out of the campaign
b : to set forcibly in motion with a blow
2 : to cause to collide
3 : to find fault with always knocking those in authority
knock cold knock dead
: to move strongly especially to admiration or applause a comedian who really knocks them dead
knock for a loop
1a : overcome knocked my opponent for a loop
b : demolish knocked our idea for a loop
2 : dumbfound, amaze the news knocked them for a loop
knock one's socks off
: to overwhelm or amaze one a performance that will knock your socks off
knock on wood
used interjectionally to ward off misfortune
knock together
: to make or assemble especially hurriedly or in a makeshift way knocked together my own bookcase



Definition of knock (Entry 2 of 2)

1a : a sharp blow : rap, hit a loud knock on the door
b(1) : a severe misfortune or hardship
(2) : setback, reversal
2a : a pounding noise
b : a sharp repetitive metallic noise caused by abnormal ignition in an automobile engine
3 : a harsh and often petty criticism the knock on him was that he couldn't handle the pressure

Examples of knock in a Sentence

Verb The ball knocked him on the chin. She knocked the glass from his hand. He knocked the baseball over the fence. The ball hit him in the mouth and knocked out one of his teeth. The wind knocked him backwards. The dog knocked against the lamp. My knee accidentally knocked against the table. Skaters were knocking into each other all over the ice. I accidentally knocked my knee against the table. Noun He gave him a knock on the head. There was a loud knock at the door. She took some knocks early in her career. He likes praise but can't stand the knocks. See More
Recent Examples on the Web: Verb While lockdowns and mandates dealt a heavy blow to the 70 percent of small businesses that shut down, the knock-out punch came when lenders—every single lender—turned off the spigot of cash, which effectively froze Main Street. Brock Blake, Forbes, 16 May 2022 Snazzy aluminum knock-off wheels added an external cue that this was no regular ’Vette, as did a sticker price nearly 40 percent higher than the base model. Robert Ross, Robb Report, 16 May 2022 If there’s one knock against Stroud’s game, it’s that his ability — and sometimes desire — to make plays with his legs is often non-existent. Stephen Means, cleveland, 13 May 2022 With over 200 positive reviews on Amazon, Uppercut is a spray that will knock your hair right into shape. John Thompson, Men's Health, 13 May 2022 Radio waves sail through the galactic plane unimpeded, but they’re obscured by the veil’s second layer—the scattering screen, a turbulent patch of space where density variations in the interstellar medium knock radio waves slightly off course. Seth Fletcher, Scientific American, 12 May 2022 Russia’s war in Ukraine has raised the price of many commodities, which can fuel knock-on instability elsewhere. Richard Vanderford, WSJ, 9 May 2022 Impressive power and authority no longer need knock your socks off. Los Angeles Times, 7 May 2022 Does the treatment knock the virus down so successfully that people aren’t generating a robust immune response? Carolyn Y. Johnson, Anchorage Daily News, 27 Apr. 2022 Recent Examples on the Web: Noun Every time there’s a knock on the door or the phone rings, Roula’s hopes are rekindled, only to be extinguished once more. Isabelle Mecattaf, The New Yorker, 13 May 2022 Black men were terrorized with, according to The Washington Post, more than 150 stop-and-frisk searches per day, public strip searches, and no-knock intrusions into homes., 13 May 2022 Eventually, Waide began asking about no-knock raids. Washington Post, 11 May 2022 The ambush shooting unfolded around 2:30 p.m. in the Ozone Park neighborhood of Queens when Torres answered a knock at her front door and was shot, authorities said. Bill Hutchinson, ABC News, 5 May 2022 The knock on affordability means first-time buyers spent a larger share of their income on a house payment than other buyers. Anna Bahney, CNN, 3 May 2022 Bryce Young, Alabama Just about the only knock on Young is his size, which Alabama lists as 6-foot, 194 pounds. Matt Young, Chron, 3 May 2022 The 19-year-old has been ruled out since January through a hamstring knock with his comeback delayed on more than one occasion. Tom Sanderson, Forbes, 30 Apr. 2022 But community anger at police flared anew in February when police officers serving a no-knock warrant shot and killed Amir Locke, a 22-year-old Black man who was staying on a couch in his cousin’s apartment. Steve Karnowski And Mohamed Ibrahim, The Christian Science Monitor, 28 Apr. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'knock.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of knock


before the 12th century, in the meaning defined at intransitive sense 1


14th century, in the meaning defined at sense 1a

History and Etymology for knock


Middle English knoken, from Old English cnocian; akin to Middle High German knochen to press

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Time Traveler for knock

Time Traveler

The first known use of knock was before the 12th century

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Last Updated

19 May 2022

Cite this Entry

“Knock.” Dictionary, Merriam-Webster, Accessed 25 May. 2022.

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More Definitions for knock


\ ˈnäk How to pronounce knock (audio) \
knocked; knocking

Kids Definition of knock

 (Entry 1 of 2)

1 : to strike in order to get someone's attention I knocked before entering.
2 : to bump against something without intending to Careful! You knocked the lamp.
3 : to make a pounding noise The car's engine began knocking.
4 : to find fault with Don't knock it till you try it.
5 : to hit forcefully He knocked the ball out of the park.
knock down
1 : to strike to the ground with or as if with a sharp blow
2 : to take apart Knock down the tent before you leave camp.
knock off
: to stop doing something Hey, I don't like that, so knock it off!
knock over
: to cause to fall



Kids Definition of knock (Entry 2 of 2)

1 : a pounding noise I heard a knock at the door.
2 : a sharp blow a knock on the head
3 : a difficult or painful experience You learn from life's knocks.


\ ˈnäk How to pronounce knock (audio) \

Medical Definition of knock

1 : a sharp blow a knock to the head
2 : a sharp pounding noise

More from Merriam-Webster on knock

Nglish: Translation of knock for Spanish Speakers

Britannica English: Translation of knock for Arabic Speakers


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