jackknife

1 of 2

noun

jack·knife ˈjak-ˌnīf

Synonyms of jackknife next

: a large strong pocketknife

: a dive executed headfirst in which the diver bends from the waist and touches the ankles while holding the knees unbent and then straightens out

jackknife

2 of 2

verb

jackknifed; jackknifing; jackknifes

intransitive verb

: to double up like a jackknife

jackknifed into a seat beside me, folding up his six feet eight—

Lady Bird Johnson

: to turn and form an angle of 90 degrees or less with each other

—used especially of a tractor-trailer combination

transitive verb

: to cause to double up like a jackknife

: to cut with a jackknife

Examples of jackknife in a Sentence

Verb The truck jackknifed on the icy road.

Recent Examples on the Web

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Noun

And the name of the game is squats: Pistol squats, goblet squats with weight, and jackknife crunches are all part of the usual regimen for Naomi. —

Jacqueline Tempera, Women's Health, 28 Apr. 2023 Nissan says the SUVs have jackknife folding keys that may not stay fully open. —

CBS News, 28 Feb. 2023

Verb

What to know 1:50 p.m.: All WB lanes on Watterson Expressway at Shelbyville Road closed after semi-truck crash All westbound lanes near the 20-mile marker on Interstate 264 are closed after a tractor trailer jackknifed on the roadway Friday afternoon. —

Marina Johnson, The Courier-Journal, 25 Jan. 2024 The big rig jackknifed approximately 20 feet off the roadway and down an embankment, according to the CHP. —

Rick Hurd, The Mercury News, 18 July 2024 See all Example Sentences for jackknife