oppositeness vs opposition

oppositeness and opposition both are nouns.

Word	Noun	Adjective	Verb	Adverb
oppositeness	Yes	No	No	No
opposition	Yes	No	No	No

As nouns, oppositeness and opposition are synonyms defined as:

oppositeness (noun)	opposition (noun)
the relation between opposed entities	the act of hostile groups opposing each other
	the action of opposing something that you disapprove or disagree with
	a body of people united in opposing something
	an armed adversary (especially a member of an opposing military force)
	a contestant that you are matched against
	a direction opposite to another
	the relation between opposed entities