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 Corpus
knife• 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.knifeknife2 verb [transitive] INJUREto put a knife into someone’s body SYN stab She had been knifed to death. —knifing noun [countable]→ See Verb tableExamples from the Corpus
knife• An electricity pylon was knocked over and one person was knifed.• Deirdre's knifed beside the sour canal..• One was a stabbing spree in which 12 cabdrivers got knifed in one week by a lone assailant.• When they met a few days later in Benghazi they quarrelled and the Zliten boy knifed the Zuwayi in the arm.• A spontaneous shiver of delight knifed through Mattie.• It is believed she was knifed to death.knifed to death• It is believed she was knifed to death.• She had been knifed to death.• The jury heard how a social worker was horrifically knifed to death on a late-night train.Origin knife1 Old English cnif 