portentous vs grandiloquent

portentous and grandiloquent both are adjectives.

Word	Noun	Adjective	Verb	Adverb
portentous	No	Yes	No	No
grandiloquent	No	Yes	No	No

As adjectives, portentous and grandiloquent are synonyms defined as:

Other synonyms of portentous include overblown, pompous, pontifical.

portentous (adjective)	grandiloquent (adjective)
puffed up with vanity	puffed up with vanity
ominously prophetic	lofty in style
of momentous or ominous significance