pretentiousness vs inelegance

pretentiousness and inelegance both are nouns.

Word	Noun	Adjective	Verb	Adverb
pretentiousness	Yes	No	No	No
inelegance	Yes	No	No	No

As nouns, inelegance is a hypernym of pretentiousness; that is, inelegance is a word with a broader meaning than pretentiousness:

pretentiousness: lack of elegance as a consequence of being pompous and puffed up with vanity
inelegance: the quality of lacking refinement and good taste

pretentiousness (noun)	inelegance (noun)
the quality of being pretentious (behaving or speaking in such a manner as to create a false appearance of great importance or worth)	the quality of lacking refinement and good taste
lack of elegance as a consequence of being pompous and puffed up with vanity