wholeheartedness vs sincerity

wholeheartedness and sincerity both are nouns.

Word	Noun	Adjective	Verb	Adverb
wholeheartedness	Yes	No	No	No
sincerity	Yes	No	No	No

As nouns, sincerity is a hypernym of wholeheartedness; that is, sincerity is a word with a broader meaning than wholeheartedness:

wholeheartedness: the quality of hearty sincerity
sincerity: the quality of being open and truthful; not deceitful or hypocritical

wholeheartedness (noun)	sincerity (noun)
the quality of hearty sincerity	the quality of being open and truthful; not deceitful or hypocritical
undivided commitment or unreserved enthusiasm	the trait of being serious
	a quality of naturalness and simplicity
	an earnest and sincere feeling