pomposity vs pompousness

pomposity and pompousness both are nouns.

Word	Noun	Adjective	Verb	Adverb
pomposity	Yes	No	No	No
pompousness	Yes	No	No	No

As nouns, pomposity and pompousness are synonyms defined as:

pomposity and pompousness: lack of elegance as a consequence of being pompous and puffed up with vanity

Other synonyms of pomposity include inflation, ostentation, ostentatiousness, pretentiousness, puffiness, splashiness.

pomposity (noun)	pompousness (noun)
lack of elegance as a consequence of being pompous and puffed up with vanity	lack of elegance as a consequence of being pompous and puffed up with vanity