grandiosity vs rant

grandiosity and rant both are nouns.

Word	Noun	Adjective	Verb	Adverb
grandiosity	Yes	No	No	No
rant	Yes	No	Yes	No

As nouns, rant is a hyponym of grandiosity; that is, rant is a word with a more specific, narrower meaning than grandiosity:

Other hyponyms of grandiosity include flourish, blah, bombast, claptrap, fustian.

grandiosity (noun)	rant (noun)
high-flown style; excessive use of verbal ornamentation	pompous or pretentious talk or writing
	a loud bombastic declamation expressed with strong emotion

grandiosity (verb)	rant (verb)
	talk in a noisy, excited, or declamatory manner