bellyful vs overabundance

bellyful and overabundance both are nouns.

Word	Noun	Adjective	Verb	Adverb
bellyful	Yes	No	No	No
overabundance	Yes	No	No	No

As nouns, overabundance is a hypernym of bellyful; that is, overabundance is a word with a broader meaning than bellyful:

Other hypernyms of bellyful include overmuch, overmuchness, superabundance.

bellyful (noun)	overabundance (noun)
an undesirable overabundance	a quantity that is more than what is appropriate
	the state of being more than full