contrary vs unfavorable

contrary is a noun but unfavorable is not a noun.

Word	Noun	Adjective	Verb	Adverb
contrary	Yes	Yes	No	No
unfavorable	No	Yes	No	No

contrary (noun)	unfavorable (noun)
exact opposition
a relation of direct opposition
a logical relation such that two propositions are contraries if both cannot be true but both can be false

contrary (adjective)	unfavorable (adjective)
of words or propositions so related that both cannot be true but both may be false	(of winds or weather) tending to hinder or oppose
very opposed in nature or character or purpose	not encouraging or approving or pleasing
resistant to guidance or discipline	involving or creating circumstances detrimental to success or effectiveness
in an opposing direction