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Noun: jackknife (jackknives)  'jak,nIf
  1. A large knife with one or more folding blades
    - clasp knife
  2. A dive in which the diver bends to touch the ankles before straightening out
Verb: jackknife  'jak,nIf
  1. (sport) dive into the water bending the body at the waist at a right angle, like a jackknife

Derived forms: jackknifes, jackknifed, jackknifing, jackknives

Type of: dive, pocket knife, pocketknife

Encyclopedia: Jackknife