impishness vs fun

impishness and fun both are nouns.

Word	Noun	Adjective	Verb	Adverb
impishness	Yes	No	No	No
fun	Yes	No	No	No

As nouns, fun is a hypernym of impishness; that is, fun is a word with a broader meaning than impishness:

Other hypernyms of impishness include playfulness.

impishness (noun)	fun (noun)
the trait of behaving like an imp	activities that are enjoyable or amusing
	violent and excited activity
	a disposition to find (or make) causes for amusement
	verbal wit or mockery (often at another's expense but not to be taken seriously)