confederative vs confederate

confederative is not a noun while confederate is a noun.

Word	Noun	Adjective	Verb	Adverb
confederative	No	Yes	No	No
confederate	Yes	Yes	Yes	No

As adjectives, confederative and confederate are synonyms defined as:

Other synonyms of confederative include allied.

confederative (noun)	confederate (noun)
	a person who joins with another in carrying out some plan (especially an unethical or illegal plan)
	someone who assists in a plot

confederative (adjective)	confederate (adjective)
united in a confederacy or league	united in a confederacy or league

confederative (verb)	confederate (verb)
	form a group or unite
	form a confederation with; of nations