playfulness vs frivolity

playfulness and frivolity both are nouns.

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

As nouns, frivolity is a hypernym of playfulness; that is, frivolity is a word with a broader meaning than playfulness:

Other hypernyms of playfulness include frivolousness.

playfulness (noun)	frivolity (noun)
activities that are enjoyable or amusing	acting like a clown or buffoon
a disposition to find (or make) causes for amusement	something of little value or significance
a festive merry feeling	the trait of being frivolous; not serious or sensible