knock
Noun pluralknocks
Formsknocks, knocking, knocked
Pluralknocks
- 1To rap with the knuckles, especially on wood, to attract attention or seek entry.
Visitors must knock loudly because the doorbell is broken.
He knocked twice and then let himself in.
Note
The everyday verb, and it wants a preposition or nothing at all: you knock on a door, knock at it, or simply knock. In John Bunyan's The Pilgrim's Progress (1678), Evangelist promises that at the gate, 'when thou knockest, it shall be told thee what thou shalt do.' Knocking is the act that waits for an answer. The older transitive use drops the preposition.
- 2An abrupt rapping sound, such as a hard object striking wood.
A sharp knock interrupted the meeting.
The hollow knock of wood on wood echoed through the hall.
Note
Behind every meaning of the word stands Old English cnocian, 'to knock, pound on, beat', which goes back through Proto-Germanic *knukōną to a root for pounding. The noun first names the sound: a knock on the door, or at it. Ashford & Simpson turn it into a figure for sudden understanding, 'It came to me, like a knock on the door', because a knock is the noise that announces an arrival.
- 3A sharp blow or impact.
She gave the door frame a knock as she carried the boxes through.
A solid knock against the rock cracked the kayak's hull.
Note
Here the knock is felt rather than heard, and its usual verb is take: you take a knock on the head. The same phrase carries over almost unchanged to the figurative setback, where plans and reputations take knocks. The bruise on the body becomes the bruise on a career, with the grammar left untouched.
- 4To criticize, belittle, or undervalue someone or something.
People knock fast food, but it serves a real purpose for busy families.
Reviewers knocked the album for repeating old ideas.
Similarcriticize, disparage, belittle, pan, slam
Note
Criticism as a blow struck with words, best known from the saying 'Don't knock it till you've tried it.' It takes a direct object: you knock a person, a product, an idea. O. Henry declines to 'knock a brother' in 1910. Norman Lindsay's The Magic Pudding warns 'A Judge you mustn't knock'. In Ralph Ellison's Invisible Man, being knocked is 'a sign you getting some place.'
- 5A criticism leveled against someone or something.
The main knock on the new phone is its short battery life.
Fair or not, the knock against the team is their weak defense.
Similarcriticism, complaint, objection, drawback
Note
Criticism imagined as a blow keeps the grammar of a blow. You take knocks, as Tom Lamont says Mumford & Sons 'take some knocks back home' in The Daily Telegraph in 2012. It is the noun partner of the verb meaning 'to belittle'. Being informal, it suits reviews and conversation better than formal argument.
- 6A blow or setback, especially one that hampers progress.
The company's reputation took a serious knock after the recall.
Each rejection was a knock, but he refused to give up.
Oppositeboost
Note
Misfortune lands like a blow to the body. In C. S. Lewis's The Lion, the Witch and the Wardrobe, Mr. Beaver calls the crumbling of the Witch's power 'a nasty knock' for her, and the pattern a knock for someone names who suffers it. Unlike the criticism sense, nothing has to be said aloud: events deliver this knock, not critics.
- 7Abnormal combustion in a spark-ignition engine caused by premature self-ignition of the fuel, and the characteristic rapping sound it produces.
Mechanics traced the persistent knock to low-octane fuel.
Engine knock can damage pistons over time.
Similarpinking, pinging, detonation
Note
Engineers use one word for two things. It names the faulty combustion itself, when fuel ignites on its own in a spark-ignition engine, and also the rapping noise that combustion makes. The name fits the noise, which echoes the sound at a door. It is uncountable: an engine has knock or suffers from knock, never 'a knock' in this sense.
- 8To have sexual intercourse with someone.
He boasted that he could knock any woman he wanted.
Word spread that he had knocked the landlord's daughter.
Similarbang, bone, bonk, mount, seduce
Note
Crude slang that treats sex as something done to a person, who appears as the direct object. Knock off is used the same way. Learners should recognize this sense rather than use it, and keep it out of anything but the most casual speech, since it reads as coarse and dismissive.
- 9A ball struck into play, especially one that results in a hit.
A crisp knock down the line brought two runners home.
The captain praised the knock that turned the game.
Note
In baseball the knock is the ball itself once it is struck into play. The word leans toward success: it is used especially of the ball that drops in for a hit, not the one that is caught. That makes it a word of credit, much as the cricket innings counts a batter's contribution.
- 10
- 11To bump against or strike something.
Be careful not to knock the glasses while you reach across the table.
She knocked her head on the low doorway.
Similarbump, bang, hit, strike
Note
The accidental blow, and it works both with and without an object: you knock against a table, or knock a drink off the bar. Used bare for a simple bump, it can sound slightly old-fashioned. It is most natural when a preposition or result says where the knock went: against, off, over.
- 12To rap upon a door in order to be let in.
She knocked the door sharply, hoping someone was still awake.
Master, knock the door hard.
c. 1594, William Shakespeare, “The Comedie of Errors”Similarrap
Note
Here the door itself is the object: you knock the door rather than knock on it. Shakespeare could write "Master, knock the door hard" in The Comedie of Errors (c. 1594), but the construction now sounds dated. In current English, add a preposition, as in knock on the door or knock at the door, which brings it close to the everyday knuckle-rapping verb. Keep the bare transitive for period flavor.
- 13To impress someone forcibly; to astonish or move them to admiration.
A turn like hers can knock even jaded critics.
His closing number knocked the packed house.
Similarwow, impress, dazzle, stun, amaze
Note
Dated British slang that turns the blow into its effect on an audience: a turn that knocks the house leaves it astonished and applauding. It runs in exactly the opposite direction from the verb of criticism, so context has to tell them apart. Because it is dated, it now reads as period color.
- 14A batter's innings in cricket; the period a player spends batting.
His patient knock anchored the innings through a difficult morning.
She brought up her century with a fluent knock.
Similarinnings
Note
Cricket slang for one batter's stay at the crease rather than the team's, usually with an adjective attached: a good knock, a patient knock. The verb is have, as in 'he had a good knock and scored well.' It belongs to casual talk about the game, while the formal word remains innings.
- 15To kick a ball toward a teammate; to pass.
Midfielders knock the ball around to keep possession.
She knocked a neat pass into the channel.
Note
Soccer's casual verb for a pass. It usually takes the ball as its object and a direction after it: knock it wide, knock a pass into the channel. Knock the ball around describes a run of short, unhurried passes. It can praise a team's patience or complain that the passing is going nowhere.
- 16To prosecute, arrest, or imprison someone under the law.
Customs will knock anyone caught smuggling goods across the border.
The agency knocked three executives for insider trading.
Similarprosecute, arrest, charge, bust, nab
Note
Street slang for being caught by the law, and most natural in the passive. In Noire's Thug-A-Licious (2006), the narrator recalls a man who figured the kids were 'too young to get knocked if we got caught.' In that same passage, get knocked sits comfortably beside busted.
- 17In cycling, sudden debilitating fatigue caused by depletion of the body's energy stores.
She felt the knock coming and quickly ate an energy gel.
The knock struck him hard on the final climb.
Similarbonk
Note
Cyclists' shorthand for the hunger knock, whose longer name says where it comes from: a rider who has run out of fuel. The short form is uncountable and usually takes the definite article, as in 'she felt the knock coming.' Riders speak of it as a familiar opponent waiting further up the road.
- 18In rummy, to end play by declaring that one's hand holds less than the allowed amount of deadwood.
Players may knock as soon as their deadwood drops below the limit.
She knocked with only three points left in her hand.
Note
A card-table verb with a precise trigger. In rummy, a player may knock once the deadwood, the leftover cards that fit no set, falls under the limit. It is intransitive: you knock, but you never knock something. Knocking ends play for everyone at the table.
Showing meanings only.
Practice
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Origin
From Middle English knokken, from Old English cnocian ("to knock, pound on, beat"), from Proto-West Germanic *knokōn and Proto-Germanic *knukōną. This traces back to a Proto-Indo-European root meaning "to squeeze, pinch, or pound," and the word is cognate with Middle High German knochen ("to hit") and Old Norse knoka.