grandiloquent

adjectives

lofty in style

"he engages in so much tall talk, one never really realizes what he is saying"

grandiloquent, magniloquent, tall

is derived from

puffed up with vanity

"a grandiloquent and boastful manner"; "overblown oratory"; "a pompous speech"; "pseudo-scientific gobbledygook and pontifical hooey"- Newsweek