From Longman Dictionary of Contemporary Englishldoce_187_fknifeknife1 /naɪf/ ●●● S3 W3 noun (plural knives /naɪvz/) [countable] 1 DDFUa metal blade fixed into a handle, used for cutting or as a weapon → scalpel a knife and fork Some young people are carrying knives to defend themselves. a kitchen knife Use a sharp knife to cut the melon into sections. → carving knife, flick knife, palette knife, paper knife, penknife2 → the knives are out (for somebody)3 → twist/turn the knife (in the wound)4 → stick/put etc the knife in/into someone5 → under the knife6 → you could cut the atmosphere/air/tension with a knife7 → like a (hot) knife through butterCOLLOCATIONSADJECTIVES/NOUN + knife sharpBe careful using that knife - it's very sharp.blunt (=not sharp)The knife was so blunt it wouldn't cut anything.a bread knifeWill you pass me the bread knife?a kitchen knife (=a long knife used for cutting vegetables etc)Every chef has his own set of kitchen knives.a carving knife (=for cutting meat)Dad always used to sharpen the carving knife.a pocket knife (=a small knife that you carry with you)He was armed with nothing but a pocket knife.knife + NOUNa knife woundShe died from a single knife wound.a knife attackHe was sentenced to 9 years in prison for a knife attack.knife crime (=crimes in which people are attacked with knives)Knife crime is on the increase.phrasesthe blade of a knifeThe blade of the knife cut cleanly through the rope. the handle of a knifeHis hand reached down to the handle of his knife.verbscarry a knife (=have it with you)The campaign warns young people about the dangers of carrying knives.be armed with a knife (=have it with you)One of the men was armed with a knife.hold a knifeIn his hand, he held a long knife.threaten somebody with a knifeThe girls were threatened with a knife.brandish/wield a knife (=wave it around in a threatening way)A man brandishing a knife burst into the room.sharpen a knife (=make it sharper)What's the best way to sharpen a knife?
Examples from the Corpusknife• The dark figure turns out to be a No. 3 male and the shiny object is a knife.• Use a knife to a criss-cross pattern through the fruit, but not through the skin.• She was working as a petrol station cashier when armed robbers threatened her with a knife during a raid.• Men fought with bottles and knives, and with guns within easy reach.• A particular knife perhaps, or some other essential-at-the-time utensil?• When her husband was fast asleep she must leave the bed, light the lamp, and get the knife.• Cleaning the inner brushes of the machine was a time-consuming affair if grease was left on the knives.