progressivity vs progressive

progressivity and progressive both are nouns.

Word	Noun	Adjective	Verb	Adverb
progressivity	Yes	No	No	No
progressive	Yes	Yes	No	No

progressivity (noun)	progressive (noun)
advancement toward better conditions or policies or methods	a person who favors a political philosophy of progress and reform and the protection of civil liberties
	a tense of verbs used in describing action that is on-going

progressivity (adjective)	progressive (adjective)
	favoring or promoting progress
	(of taxes) adjusted so that the rate increases as the amount of income increases
	advancing in severity
	gradually advancing in extent
	favoring or promoting reform (often by government action)
	(of a card game or a dance) involving a series of sections for which the participants successively change place or relative position