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[nok] /nɒk/
verb (used without object)
to strike a sounding blow with the fist, knuckles, or anything hard, especially on a door, window, or the like, as in seeking admittance, calling attention, or giving a signal:
to knock on the door before entering.
to strike in collision; bump:
He knocked into a table.
to make a pounding noise:
The engine of our car is knocking badly.
Informal. to engage in trivial or carping criticism; find fault.
Cards. to end a game, as in gin rummy, by laying down a hand in which those cards not included in sets total less than a specific amount.
verb (used with object)
to give a sounding or forcible blow to; hit; strike; beat.
to drive, force, or render by a blow or blows:
to knock a man senseless.
to make by striking a blow or blows:
to knock a hole in the wall.
to strike (a thing) against something else.
Informal. to criticize, especially in a carping manner:
He's always knocking everything.
British Slang. to astound; impress greatly.
an act or instance of knocking.
the sound of knocking, especially a rap, as at a door.
a blow or thump.
Informal. an adverse criticism.
the noise resulting from faulty combustion or from incorrect functioning of some part of an internal-combustion engine.
Cricket. an innings.
British Slang.
  1. one of a combination of dealers who bid together, rather than against each other, at an auction, and later resell the purchases among themselves.
  2. an auction at which this is done.
  3. the sale of merchandise recently obtained by a dealer at an auction.
Verb phrases
knock around/about, Informal.
  1. to wander aimlessly or idly; loaf.
  2. to mistreat (someone), especially physically.
  3. to jar; shake up.
knock back, Slang. to drink (a beverage), especially quickly and heartily:
He knocked back two shots of vodka.
knock down,
  1. to sell at auction by a blow of the hammer or to a bidder.
  2. to take apart or disassemble, as for facility in handling, storing, shipping, etc.
  3. Slang. to receive, as a salary or a scholastic grade; earn:
    He knocks down 30 grand a year.
  4. Informal. to lower the price of; reduce:
    to knock down end-of-season leftovers.
  5. Slang. to embezzle or steal (money).
  6. to cause (a sailing vessel) to heel, as by a gust of wind, to such a degree that it cannot right itself.
knock off,
  1. Informal. to cease activity, especially work:
    to knock off at five every day.
  2. to stop doing something; quit:
    Knock it off or you'll get into a mess.
  3. Slang. to dispose of; finish.
  4. Slang. to murder; kill.
  5. Slang. to die.
  6. Slang. to get rid of; reduce.
  7. Slang. to disable or defeat.
  8. Slang. to commit a robbery at; steal from:
    The gang knocked off a gas station.
  9. Nautical Slang. to blow the head (of a sailing vessel) off the wind.
  10. to imitate, copy, or plagiarize:
    to knock off designer dresses in cheap materials.
knock out,
  1. to defeat (an opponent) in a boxing match by striking such a blow that the opponent is unable to rise within the specified time.
  2. to render (a person) unconscious:
    Those sleeping pills knocked me out for ten hours.
  3. to make tired or exhausted:
    Christmas shopping always knocks me out.
  4. Informal. to produce quickly, hurriedly, or with ease:
    He knocks out two poems a day.
  5. to damage or destroy:
    The explosion knocked out the power for several hours.
  6. knock (def 28).
knock over,
  1. to strike (someone or something) from an erect to a prone position:
    to knock over a lamp.
  2. to distress; overcome:
    When the announcement came we were completely knocked over.
  3. Slang. to rob, burglarize, or hijack:
    He knocked over five banks.
knock together, to make or construct in a hurry or with little attention to detail:
He knocked together a couple of tables.
knock up,
  1. Slang. to make pregnant.
  2. to exhaust; weary; tire.
  3. to damage; mar:
    The children knocked up the new table.
  4. to injure; wound:
    He was afraid to come home from school all knocked up again.
  5. British. to wake up; rouse; call:
    He knocked us up before dawn.
have it knocked, Slang. to be assured of success:
With a government job, he thought he had it knocked.
knock out of the box, Baseball. to cause a pitcher to be removed from the box because the pitcher has permitted too many hits to be made.
Also, knock out.
knock the / one's socks off, Informal. to have an overwhelming effect on:
The song knocked the socks off the audience.
Origin of knock
before 1000; 1890-95 for def 4; Middle English knokken, knoken (v.), Old English cnocian, cnucian; cognate with Old Norse knoka to thump, knock
Related forms
knockless, adjective
reknock, verb
unknocked, adjective
unknocking, adjective
1. See strike. Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
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Examples from the Web for knock up
Historical Examples
  • But drop or, as you say in England, knock up calling me ‘sir.’

    The Island Mystery George A. Birmingham
  • I determined to knock up the lodge-keeper, and to enlist her assistance.

    A Master of Mysteries L. T. Meade
  • If he looks shocked at the suggestion, Dick can knock up a partition.

    They and I Jerome K. Jerome
  • I mean to get a stone and knock up some of the bricks, if I can, and see.

    Rollo in Rome Jacob Abbott
  • All he has to do is to knock up a book of travels, and it'll go like wildfire.'

    The Whirlpool George Gissing
  • It might freeze—I could sprain my ankle, or knock up an excuse of some sort.

  • If you play polo hard enough, you may knock up a pony every game.

    The Golden Butterfly Walter Besant
  • It wasn't so late but Bill could go into the town and knock up the folks at a hotel.

    Vision House C. N. Williamson
  • If you want to beat the enemy, you must knock up the revenue.

    Sybil Benjamin Disraeli
  • When the chance comes, I'm bound to kick around a bit and knock up the dust.

    Menotah Ernest G. Henham
British Dictionary definitions for knock up

knock up

verb (adverb, mainly transitive)
(informal) Also knock together. to assemble quickly; improvise: to knock up a set of shelves
(Brit, informal) to waken; rouse: to knock someone up early
(slang) to make pregnant
(Brit, informal) to exhaust: the heavy work knocked him up
(cricket) to score (runs)
(intransitive) (tennis, squash, badminton) to practise or hit the ball about informally, esp before a match
a practice session at tennis, squash, or a similar game


(transitive) to give a blow or push to; strike
(intransitive) to rap sharply with the knuckles, a hard object, etc, esp to capture attention: to knock at the door
(transitive) to make or force by striking: to knock a hole in the wall
(intransitive) usually foll by against. to collide (with)
(transitive) to bring into a certain condition by hitting or pushing: to knock someone unconscious
(transitive) (informal) to criticize adversely; belittle: to knock someone's work
(intransitive) Also pink. (of an internal-combustion engine) to emit a characteristic metallic noise as a result of faulty combustion
(intransitive) (of a bearing, esp one in an engine) to emit a regular characteristic sound as a result of wear
(Brit, slang) to have sexual intercourse with (a person)
(informal) knock a person into the middle of next week, to hit a person with a very heavy blow
knock one's head against, to have a violent or unpleasant encounter with (adverse facts or circumstances)
knock on the head
  1. to daze or kill (a person) by striking on the head
  2. effectively to prevent the further development of (a plan)
  1. a blow, push, or rap: he gave the table a knock
  2. the sound so caused
the sound of knocking in an engine or bearing
(informal) a misfortune, rebuff, or setback
(informal) unfavourable criticism
(informal) (in cricket) an innings or a spell of batting
Word Origin
Old English cnocian, of imitative origin; related to Old Norse knoka to hit
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for knock up

1660s in sense of "arouse by knocking at the door," from knock (v.). However it is little used in this sense in American English, where the phrase means "get a woman pregnant" (1813), possibly ultimately from knock "to copulate with" (1590s; cf. slang knocking-shop "brothel," 1860).

Knocked up in the United States, amongst females, the phrase is equivalent to being enciente, so that Englishmen often unconsciously commit themselves when amongst our Yankee cousins. [John Camden Hotten, "The Slang Dictionary," London, 1860]



Old English cnocian (West Saxon cnucian), "to pound, beat; knock (on a door)," likely of imitative origin. Meaning "deprecate, put down" is from 1892. Related: Knocked; knocking. Knock-kneed first attested 1774. Knock-down, drag-out is from 1827. Command knock it off "stop it" is first recorded 1880, perhaps from auctioneer's term for "dispose of quickly:"

At the commencement of the sales, he gave every one that wanted to purchase a paper containing a description of the lands that were to be sold; and, as the sales were cried, he called over the numbers and described the land; and when it got up to one dollar and a quarter an acre, if no body bid, after it was cried two or three times, he would say, knock it off, knock it off. [U.S. Senate record, 1834]



mid-14c., from knock (v.). As an engine noise, from 1899.

Online Etymology Dictionary, © 2010 Douglas Harper
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Slang definitions & phrases for knock up



: It wasn't a disinterested comment—it was a knock/ The knock on Fernandez is he can't field


  1. To deprecate; criticize severely; dispraise; PUT someone or something DOWN: by knocking Hymie Salzman (1896+)
  2. To borrow or lend; ask or beg (1950s+ Black)
  3. To give: C'mon, baby, knock me a kiss (1944+ Black)

Related Terms

don't knock it, have something cinched

The Dictionary of American Slang, Fourth Edition by Barbara Ann Kipfer, PhD. and Robert L. Chapman, Ph.D.
Copyright (C) 2007 by HarperCollins Publishers.
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Idioms and Phrases with knock up

knock up

Make pregnant, as in The young girl said she was afraid of getting knocked up. [ ; early 1800s ]
Injure or damage, as in This coffee table got all knocked up in the moving van.
The American Heritage® Idioms Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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