levity vs playfulness

levity and playfulness both are nouns.

Word	Noun	Adjective	Verb	Adverb
levity	Yes	No	No	No
playfulness	Yes	No	No	No

As nouns, playfulness is a hyponym of levity; that is, playfulness is a word with a more specific, narrower meaning than levity:

Other hyponyms of levity include gaiety.

levity (noun)	playfulness (noun)
a manner lacking seriousness	activities that are enjoyable or amusing
feeling an inappropriate lack of seriousness	a disposition to find (or make) causes for amusement
	a festive merry feeling