[ nahyf ]
See synonyms for: knifeknifingknivesknifelike on

noun,plural knives [nahyvz]. /naɪvz/.
  1. an instrument for cutting, consisting essentially of a thin, sharp-edged, metal blade fitted with a handle.

  2. a knifelike weapon; dagger or short sword.

  1. any blade for cutting, as in a tool or machine.

verb (used with object),knifed, knif·ing.
  1. to apply a knife to; cut, stab, etc., with a knife.

  2. to attempt to defeat or undermine in a secret or underhanded way.

verb (used without object),knifed, knif·ing.
  1. to move or cleave through something with or as if with a knife: The ship knifed through the heavy seas.

Idioms about knife

  1. 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

Other words from knife

  • knifelike, adjective
  • knifer, noun

Words Nearby knife Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use knife in a sentence

British Dictionary definitions for knife


/ (naɪf) /

nounplural knives (naɪvz)
  1. a cutting instrument consisting of a sharp-edged often pointed blade of metal fitted into a handle or onto a machine

  2. a similar instrument used as a weapon

  1. have one's knife in someone to have a grudge against or victimize someone

  2. twist the knife to make a bad situation worse in a deliberately malicious way

  3. the knives are out for someone British people are determined to harm or put a stop to someone: the knives are out for Stevens

  4. under the knife undergoing a surgical operation

  1. to cut, stab, or kill with a knife

  2. to betray, injure, or depose in an underhand way

Origin of knife

Old English cnīf; related to Old Norse knīfr, Middle Low German knīf

Derived forms of knife

  • knifelike, adjective
  • knifer, noun

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Idioms and Phrases with knife


see at gunpoint (knifepoint); under the knife; you could cut it with a knife.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.