irresolution vs incertitude

irresolution and incertitude both are nouns.

Word	Noun	Adjective	Verb	Adverb
irresolution	Yes	No	No	No
incertitude	Yes	No	No	No

As nouns, incertitude is a hypernym of irresolution; that is, incertitude is a word with a broader meaning than irresolution:

irresolution: doubt concerning two or more possible alternatives or courses of action
incertitude: the state of being unsure of something

Other hypernyms of irresolution include doubt, doubtfulness, dubiety, dubiousness, uncertainty.

irresolution (noun)	incertitude (noun)
the trait of being irresolute; lacking firmness of purpose	the state of being unsure of something
doubt concerning two or more possible alternatives or courses of action