agreeableness vs agreeable

agreeableness is a noun but agreeable is not a noun.

Word	Noun	Adjective	Verb	Adverb
agreeableness	Yes	No	No	No
agreeable	No	Yes	No	No

agreeableness (noun)	agreeable (noun)
a temperamental disposition to be agreeable
pleasantness resulting from agreeable conditions

agreeableness (adjective)	agreeable (adjective)
	conforming to your own liking or feelings or nature
	prepared to agree or consent
	in keeping