whimsicality vs fun

whimsicality and fun both are nouns.

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

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

Other hypernyms of whimsicality include playfulness.

whimsicality (noun)	fun (noun)
the trait of behaving like an imp	activities that are enjoyable or amusing
the trait of acting unpredictably and more from whim or caprice than from reason or judgment	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)