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bring a knife to a gunfight

To come poorly prepared or equipped for some task, goal, competition, or confrontation. Often used in the negative as a forewarning or piece of advice. Make sure you have researched your position thoroughly and comprehensively before the debate. You don't want to bring a knife to a gunfight. If you haven't studied law, representing yourself in court is like bringing a knife to a gunfight.
See also: bring, knife

a knife in the back

A grievous or supreme act of treachery or betrayal. (Usually preceding "of/for (someone).") This revelation regarding the governor's longstanding misappropriation of public funds is sure to be a knife in the back of his constituency, as well as every taxpayer in the state.
See also: back, knife

before you can say "knife"

Very quickly. I'll have the files done before you can say "knife."
See also: before, can, say


1. noun A stressful situation or mindset. I am on a knife-edge right now, waiting to hear if my contract has been extended—if not, I'll need to find a new job. Our grandmother is very ill, so we are all on a knife-edge these days.
2. adjective Very crisply and neatly folded. Typically said of the pleats of a garment or textile. When you fold that tablecloth, I need to see knife-edge pleats in it! That dry-cleaner does a great job getting a knife-edge crease in my pants.
3. adjective Sharp, narrow, and hard to traverse. Typically said of topographic features, like mountains. That knife-edge mountain pass has 1,000-foot drops on either side.

play a good knife and fork

To eat vigorously. My, you're playing a good knife and fork tonight—you must be hungry!
See also: and, fork, good, knife, play

go under the knife

Fig. to submit to surgery; to have surgery done on oneself. She goes under the knife tomorrow for her gallbladder. Frank lives in constant fear of having to go under the knife.
See also: knife

pull a gun (on someone)

 and pull a knife (on someone)
to bring out a gun or knife suddenly so that it is ready for use against someone. I screamed when the mugger pulled a knife on me. The police shot the thief when he pulled a gun.
See also: gun, pull

pull a knife

(on someone) Go to pull a gun (on someone).
See also: knife, pull

twist the knife

also turn the knife
to do or say something to make a situation worse He caused McCarthy to make a fool of himself, and then twisted the knife by asking, “Have you no decency, sir?”
Usage notes: also used in the form a twist of the knife: When discussing the union, even when he starts by saying positive things George can never resist a twist of the knife.
See also: knife, twist

under the knife

having a medical operation I wouldn't go under the knife just to improve my appearance.
Usage notes: most often used with the verbs go or be, as in the example
See also: knife

you could cut the atmosphere with a knife

something that you say to describe a situation in which everyone is feeling very angry or nervous and you feel that something unpleasant could soon happen There was a lot of tension between Diane and Carol; you could cut the atmosphere in that room with a knife.
See Fish or cut bait, cut through like a knife through butter, to cut a long story short
See also: atmosphere, could, cut, knife

cut/go through something like a (hot) knife through butter

to cut something very easily A laser beam can cut through metal like a hot knife through butter.
See also: butter, cut, knife, like

go under the knife

to have a medical operation More and more women are choosing to go under the knife just to improve their appearance. (humorous)
See also: knife

have your knife into somebody

  (British & Australian informal)
to try to cause problems for someone because you do not like them Mike's had his knife into me ever since he found out I was seeing his ex-girlfriend.
See also: have, knife

put/stick the knife in

  (British & Australian informal)
to do or say something unpleasant to someone in an unkind way 'No one in the office likes you, you know, Tim', she said, putting the knife in. The reviewer from The Times really stuck the knife in, calling it the worst play he'd seen in years.
See also: knife, put

turn/twist the knife

to do or say something unpleasant which makes someone who is already upset feel worse Having made the poor girl cry, he twisted the knife by saying she was weak and unable to cope with pressure.
See also: knife, turn

on a knife-edge

if a person or organization is on a knife-edge, they are in a difficult situation and are worried about what will happen in the future She's been living on a knife-edge since her ex-husband was released from prison last month. The theatre is on a financial knife-edge and must sell 75% of its seats every night to survive.
See also: on

under the knife

Undergoing surgery, as in He was awake the entire time he was under the knife. The phrase is often put as go under the knife meaning "be operated on," as in When do you go under the knife? Knife standing for "surgery" was first recorded in 1880.
See also: knife

you could cut it with a knife

Alluding to something very thick, such as muggy air or a heavy accent; also, a very tense atmosphere. For example, The smoke was so thick you could cut it with a knife, or When I walked in they all stopped talking and you could cut the air with a knife. [Colloquial; late 1800s]
See also: could, cut, knife

long knife

1. n. an assassin. (Underworld.) Some long knife showed up, but Marty took him out before he made his move.
2. n. a destroyer; a hatchet man. One of his long knives came over to pressure us into cooperating.
See also: knife, long

under the knife

Undergoing surgery.
See also: knife
References in classic literature ?
You know that wonderful Indian knife that the twins have been making such a to-do about?
Then he turned, picked up Won-tolla's trail where he had left it, settled himself in a tree with an outrunning branch some eight feet from the ground, and sat still, sharpening his knife on the sole of his foot and singing to himself.
His wife tells us that the knife had lain upon the dressing-table, and that he had picked it up as he left the room.
He had absently taken up the knife a second time, and again Rogojin snatched it from his hand, and threw it down on the table.
The fellow pitted against Juag was a veritable giant; he was hack-ing and hewing away at the poor slave with a villainous-looking knife that might have been designed for butch-ering mastodons.
If you don't get us on our way by tomorrow you'll never have another chance to lie, for I heard two of the men saying that they'd like to run a knife into you and that if you kept them in this hole any longer they'd do it.
My name was called in a low voice, and a man stepped out beside me as I halted with raised knife.
Her voice was soft and musical--Tarzan could scarce realize that its possessor in a moment more would be transformed by the fanatical ecstasy of religious zeal into a wild-eyed and bloodthirsty executioner, who, with dripping knife, would be the first to drink her victim's red, warm blood from the little golden cup that stood upon the altar.
The fetish man waved his hands and drew a step nearer to Trent, his knife outstretched.
Two turnkeys, an inspector, and three or four guards, made their appearance all at once, and found Cornelius still using the stick, with the knife under his foot.
Gogoomy have long knife one hand, and Kwaque's head in other hand.
And then she drew out a knife, the blade of which shone so that it was quite dreadful to behold.
He took from his tail-pocket a long horn-hilted knife with a red smear on it, and handed it politely to the sergeant.
There was only one galley knife that, as a knife, amounted to anything.
Anna answered a few words, but not foreseeing any entertainment from the conversation, she asked Annushka to get a lamp, hooked it onto the arm of her seat, and took from her bag a paper knife and an English novel.