knife

1 of 2

noun

ˈnīf 

plural knives ˈnīvz 

often attributive

1

a

: a cutting instrument consisting of a sharp blade fastened to a handle

b

: a weapon or tool resembling a knife

2

: a sharp cutting blade or tool in a machine

3

: surgery sense 4

—usually used in the phrase under the knife

knifelike

ˈnīf-ˌlīk 

adjective

knife

2 of 2

verb

knifed; knifing

transitive verb

1

: to use a knife on

specifically : to stab, slash, or wound with a knife

2

: to cut, mark, or spread with a knife

3

: to try to defeat by underhanded means

4

: to move like a knife in

birds knifing the autumn sky

intransitive verb

: to cut a way with or as if with a knife blade

the cruiser knifed through the heavy seas

Synonyms of knife

Noun

• cutter
• blade
• dagger

Examples of knife in a Sentence

Noun

Each dinner guest gets two forks, a knife, and a spoon.

He pulled a knife on me and threatened to stab me with it.

Verb

He died after being knifed in the chest.

ships knifing through the waves

Recent Examples on the Web

Noun

Prosecutors charged Martinez in 2017 with the murder of 32-year-old Daniel Reyes, as well as with felony enhancements for allegedly lying in wait and for using a knife. —Clara Harter, Los Angeles Times, 10 Jan. 2026

Her father found her inside their home with a knife sticking out of her neck and signs of struggle in multiple rooms. —Michael Ruiz, FOXNews.com, 10 Jan. 2026

Verb

De’Anthony Melton was once again spectacular as a scorer, knifing into the paint for layups with a quick first step and burying four 3-pointers with a confident jump shot. —Joseph Dycus, Mercury News, 14 Jan. 2026

What separates the 6-foot-3, 220-pound Emmanwori from others is his ability to cover any of the five eligible receivers on any play, while also setting the edge against tight ends in the run game and knifing into the backfield to take down runners. —Mike Sando, New York Times, 12 Jan. 2026

Word History

Etymology

Noun

Middle English knif, from Old English cnīf, perhaps from Old Norse knīfr; akin to Middle Low German knīf knife

First Known Use

Noun

before the 12th century, in the meaning defined at sense 1a

Verb

1865, in the meaning defined at transitive sense 1

Phrases Containing knife

• bowie knife
• butter knife
• carving knife
• case knife
• chef's knife
• clasp knife
• flick-knife
• going under the knife
• go under the knife
• knife-edge
• like a (hot) knife through butter
• on a/the knife-edge
• palette knife
• paper knife
• paring knife
• putty knife
• sheath knife
• so thick you could cut it with a knife
• steak knife
• switch knife
• twist/turn the knife (in the wound)
• utility knife
• you could cut it with a knife

Rhymes for knife

• life
• rife
• strife
• wife
• afterlife
• pocketknife
• alewife
• birdlife
• folklife
• housewife
• jackknife
• loosestrife

Kids Definition

knife

1 of 2 noun

ˈnīf 

plural knives ˈnīvz 

1

: a cutting instrument consisting of a sharp blade fastened to a handle

2

: a cutting blade in a machine

knife

2 of 2 verb

knifed; knifing

1

: to stab, slash, or wound with a knife

2

: to move like a knife

ships knifing through the sea

Medical Definition

knife

noun

ˈnīf 

plural knives ˈnīvz 

1

: any of various instruments used in surgery primarily to sever tissues: as

a

: a cutting instrument consisting of a sharp blade attached to a handle

b

: an instrument that cuts by means of an electric current

2

: surgery sense 3

—usually used in the phrase under the knife

went under the knife yesterday

was afraid of the knife