impracticality vs uselessness

impracticality and uselessness both are nouns.

Word	Noun	Adjective	Verb	Adverb
impracticality	Yes	No	No	No
uselessness	Yes	No	No	No

As nouns, uselessness is a hypernym of impracticality; that is, uselessness is a word with a broader meaning than impracticality:

impracticality: concerned with theoretical possibilities rather than actual use
uselessness: the quality of having no practical use

Other hypernyms of impracticality include inutility, unusefulness.

impracticality (noun)	uselessness (noun)
concerned with theoretical possibilities rather than actual use	the quality of having no practical use