n.
1.a large knife with one or more folding blades
2.a dive in which the diver bends to touch the ankles before straightening out jackknife v.
1.dive into the water bending the body at the waist at a right angle, like a jackknife
Idiom of the Day
make (something) up to (someone)
to repay someone for something, to make amends to someone
I was late for work so I had to make it up to my boss by working late.