jolliness vs merriment

jolliness and merriment both are nouns.

Word	Noun	Adjective	Verb	Adverb
jolliness	Yes	No	No	No
merriment	Yes	No	No	No

As nouns, merriment is a hypernym of jolliness; that is, merriment is a word with a broader meaning than jolliness:

Other hypernyms of jolliness include gaiety, amiability, good humor, good humour, good temper.

jolliness (noun)	merriment (noun)
feeling jolly and jovial and full of good humor	activities that are enjoyable or amusing
	a gay feeling