jackknife vs diving

jackknife and diving both are nouns.

Word	Noun	Adjective	Verb	Adverb
jackknife	Yes	No	Yes	No
diving	Yes	No	No	No

As nouns, diving is a hypernym of jackknife; that is, diving is a word with a broader meaning than jackknife:

jackknife: a dive in which the diver bends to touch the ankles before straightening out
diving: a headlong plunge into water

Other hypernyms of jackknife include dive.

jackknife (noun)	diving (noun)
a dive in which the diver bends to touch the ankles before straightening out	a headlong plunge into water
a large knife with one or more folding blades	an athletic competition that involves diving into water

jackknife (verb)	diving (verb)
dive into the water bending the body at the waist at a right angle, like a jackknife