irrevocability vs decisiveness

irrevocability and decisiveness both are nouns.

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

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

irrevocability: The state or condition of being impossible to retract or reverse; finality.
decisiveness: the quality of being final or definitely settled

Other hypernyms of irrevocability include conclusiveness, finality.

irrevocability (noun)	decisiveness (noun)
The state or condition of being impossible to retract or reverse; finality.	the trait of resoluteness as evidenced by firmness of character or purpose
	the quality of being final or definitely settled