WORD ORIGIN | IDIOMS noun, plural knives . [nahyvz] /naɪvz/ an instrument for cutting, consisting essentially of a thin, sharp-edged, metal blade fitted with a handle. a knifelike weapon; dagger or short sword. any blade for cutting, as in a tool or machine. verb (used with object), knifed, knif·ing. to apply a knife to; cut, stab, etc., with a knife. to attempt to defeat or undermine in a secret or underhanded way. verb (used without object), knifed, knif·ing. to move or cleave through something with or as if with a knife: The ship knifed through the heavy seas. Idioms under the knife, in surgery; undergoing a medical operation: The patient was under the knife for four hours. Origin of knife before 1100; Middle English knif, Old English cnīf; cognate with Dutch knijf, German Kneif, Old Norse knīfr Related forms knife·like, adjective knif·er, noun
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for under the knife noun plural knives ( naɪvz) a cutting instrument consisting of a sharp-edged often pointed blade of metal fitted into a handle or onto a machine a similar instrument used as a weapon have one's knife in someone to have a grudge against or victimize someone twist the knife to make a bad situation worse in a deliberately malicious way the knives are out for someone British people are determined to harm or put a stop to someone the knives are out for Stevens under the knife undergoing a surgical operation verb (tr) to cut, stab, or kill with a knife to betray, injure, or depose in an underhand way Derived Forms knifelike, adjective knifer, noun Word Origin for knife
cnīf; related to Old Norse knīfr, Middle Low German knīf
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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Word Origin and History for under the knife n.
late Old English
cnif, probably from Old Norse knifr, from Proto-Germanic *knibaz (cf. Middle Low German knif, Middle Dutch cnijf, German kneif), of uncertain origin. To further confuse the etymology, there also are forms in -p-, e.g. Dutch knijp, German kneip. French canif "penknife" (mid-15c.) is borrowed from Middle English or Norse. v.
knife (n.). Related: Knifed; knifing.
Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with 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 at gunpoint (knifepoint); under the knife; you could cut it with a knife.
The American Heritage® Idioms Dictionary
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