noun. a large knife with one or more folding blades.
- clasp knife
noun. black-and-white drumfish with an erect elongated dorsal fin.
- genus Equetus
noun. a dive in which the diver bends to touch the ankles before straightening out.
verb. dive into the water bending the body at the waist at a right angle, like a jackknife.
Sentences with jackknife
1. Verb, base form
Avoid exaggerated turns, which can cause your trailer and vehicle to buckle or jackknife, necessitating another attempt.
2. Noun, singular or mass
For a jackknife, hold one knee to the chest and lean backwards for a directed splash.
To tighten your tummy and strengthen your core, Bodybuilding.com recommends butt-ups, crunches, bent-knee hip raises, jackknife sit-ups and the cross-body crunch, which is similar to an air bike.
4. Adjective, comparative
Try incline situps on an incline bench or do jackknife situps from the floor.