frivolity vs japery

frivolity and japery both are nouns.

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

As nouns, frivolity and japery are synonyms defined as:

Other synonyms of frivolity include buffoonery, clowning, harlequinade, prank.

frivolity (noun)	japery (noun)
acting like a clown or buffoon	acting like a clown or buffoon
something of little value or significance
the trait of being frivolous; not serious or sensible