\ 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

Keep scrolling for more

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 The custom of sending treats seems to have been comes from the United Kingdom and might be associated with a legendary character named Jack Valentine, who would supposedly knock on the back doors of homes and leave treats for children in Norfolk. Janet B. Carson, Arkansas Online, "Happy Valentine's Day," 15 Feb. 2021 People have to knock on one another’s doors to send messages, so spreading misinformation would take more effort. New York Times, "Are Private Messaging Apps the Next Misinformation Hot Spot?," 3 Feb. 2021 Before November, Democrats did not knock on doors because of the pandemic, instead relying on texting, phone banking and virtual organizing. Los Angeles Times, "Essential Politics: How Georgia upended expectations," 6 Jan. 2021 The suit, filed in a Tarrant County court against the city of Fort Worth, alleges that officers gave no verbal warning and did not knock before forcing their way into the home. Minyvonne Burke, NBC News, "69-year-old Black woman sues city, claims Texas police 'smashed' into home for 'no reason'," 9 Dec. 2020 If the corporate elites lock you out of the boardroom, don’t knock politely to be allowed inside. Joseph Goodman |, al, "Shunned BYU kicks down door to College Football Playoff conversation," 4 Dec. 2020 Perhaps Bramlett’s right hook didn’t just knock Costello off a barstool and the charts. David A. Graham, The Atlantic, "Why a 41-Year-Old Record About Fascism Matters Now," 30 Nov. 2020 Everton was the last side to relinquish its undefeated record in this most unpredictable of seasons, though the 2-0 loss at Southampton didn't knock Carlo Ancelotti's side off the top of the standings on Sunday. Steve Douglas, Star Tribune, "Everton loses last unbeaten record in unpredictable EPL," 25 Oct. 2020 Veteran incumbent and Republican Chris Monzel lost to a relatively unknown Democrat, Stephanie Summerow Dumas, who did not knock on any doors or raise much money. Scott Wartman, The Enquirer, "Democrats seek to stay in complete control of Hamilton County commission. Here's what you should know about this key race.," 14 Oct. 2020 Recent Examples on the Web: Noun The no-knock warrants, which allow officers to burst into a home without announcing, have since been banned by Louisville's Metro Council in a law named for Taylor. Dylan Lovan, Star Tribune, "Kentucky to study warrant process after Taylor shooting," 21 Jan. 2021 In July, police officials pushed back against efforts to abolish or curtail their no-knock warrants — helping carve out a wide range of investigations for which they could still be used. Washington Post, "Maryland SWAT officer cleared in fatal shooting of Duncan Lemp during execution of no-knock warrant," 31 Dec. 2020 Breonna’s Law would end the use of no-knock warrants across the entire state. Anoa Changa, Essence, "‘Slow Justice’ As Officers Responsible For Killing Breonna Taylor Face Possible Termination," 30 Dec. 2020 Following the raid, Louisville officials banned the use of no-knock warrants, which allow the police to forcibly enter people’s homes to search them without warning. New York Times, "Louisville Officer Who Shot Breonna Taylor Will Be Fired," 29 Dec. 2020 The Pima County Sheriff's Office agreed to limit no-knock warrants., "The biggest Arizona headlines of 2020, from COVID-19 to the elections," 28 Dec. 2020 In June, the Louisville Metro Council passed 'Breonna's Law,' which bans no-knock warrants. Simret Aklilu, CNN, "Petitions for George Floyd and Breonna Taylor are the most signed pleas of all time at," 24 Dec. 2020 The legislative panel also discussed the state's citizens' arrest, no-knock warrants and use-of-force policies but has not drafted concrete legislative proposals. Nyamekye Daniel, Washington Examiner, "Georgia lawmakers examine police accountability, qualified immunity," 23 Dec. 2020 Various cities and counties across the country have passed bans on chokeholds and no-knock warrants. Washington Post, "Fatal shooting of Casey Goodson reignites scrutiny of efforts to overhaul policing," 17 Dec. 2020

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.

See More

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

Keep scrolling for more

Learn More about knock

Time Traveler for knock

Time Traveler

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

See more words from the same century

Statistics for knock

Last Updated

24 Feb 2021

Cite this Entry

“Knock.” Dictionary, Merriam-Webster, Accessed 2 Mar. 2021.

Style: MLA
MLA Chicago APA Merriam-Webster

Keep scrolling for more

More Definitions for knock



English Language Learners Definition of knock

 (Entry 1 of 2)

: to hit something (such as a door) with the knuckles of your hand or with a hard object (such as a knocker) in order to get people's attention
: to hit (something or someone) in a forceful way
: to touch or hit someone or something in a way that is not planned or intended



English Language Learners Definition of knock (Entry 2 of 2)

: a hard, sharp hit
: the sound made by a hard hit
informal : an experience that makes you less confident or successful for a period of time : a difficult or painful experience


\ 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

Keep scrolling for more

More from Merriam-Webster on knock

Thesaurus: All synonyms and antonyms for knock

Nglish: Translation of knock for Spanish Speakers

Britannica English: Translation of knock for Arabic Speakers

Comments on knock

What made you want to look up knock? Please tell us where you read or heard it (including the quote, if possible).


Test Your Vocabulary

February 2021 Words of the Day Quiz

  • squirrel in winter
  • Which is a synonym of perdure?
True or False

Test your knowledge - and maybe learn something along the way.

Universal Daily Crossword

A daily challenge for crossword fanatics.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!