plenteousness vs plenty

plenteousness and plenty both are nouns.

Word	Noun	Adjective	Verb	Adverb
plenteousness	Yes	No	No	No
plenty	Yes	No	No	Yes

As nouns, plenteousness and plenty are synonyms defined as:

Other synonyms of plenteousness include plenitude, plentifulness, plentitude.

plenteousness (noun)	plenty (noun)
a full supply	a full supply
	(often followed by `of') a large number or amount or extent

plenteousness (adverb)	plenty (adverb)
	as much as necessary