inapplicability vs irrelevance

inapplicability and irrelevance both are nouns.

Word	Noun	Adjective	Verb	Adverb
inapplicability	Yes	No	No	No
irrelevance	Yes	No	No	No

As nouns, irrelevance is a hypernym of inapplicability; that is, irrelevance is a word with a broader meaning than inapplicability:

inapplicability: irrelevance by virtue of being inapplicable to the matter at hand
irrelevance: the lack of a relation of something to the matter at hand

Other hypernyms of inapplicability include irrelevancy.

inapplicability (noun)	irrelevance (noun)
irrelevance by virtue of being inapplicable to the matter at hand	the lack of a relation of something to the matter at hand