decisiveness vs resolve

decisiveness and resolve both are nouns.

Word	Noun	Adjective	Verb	Adverb
decisiveness	Yes	No	No	No
resolve	Yes	No	Yes	No

As nouns, resolve is a hypernym of decisiveness; that is, resolve is a word with a broader meaning than decisiveness:

decisiveness: the trait of resoluteness as evidenced by firmness of character or purpose
resolve: the trait of being resolute

Other hypernyms of decisiveness include firmness, firmness of purpose, resoluteness, resolution.

decisiveness (noun)	resolve (noun)
the trait of resoluteness as evidenced by firmness of character or purpose	the trait of being resolute
the quality of being final or definitely settled	a formal expression by a meeting; agreed to by a vote

decisiveness (verb)	resolve (verb)
	cause to go into a solution
	bring to an end; settle conclusively
	reach a decision
	find the solution
	understand the meaning of
	reach a conclusion after a discussion or deliberation
	make clearly visible