lofty in style
"he engages in so much tall talk, one never really realizes what he is saying"
puffed up with vanity
"a grandiloquent and boastful manner"
"overblown oratory"
"a pompous speech"
"pseudo-scientific gobbledygook and pontifical hooey"
Given to using language in a showy way by using an excessive amount of difficult words to impress others; bombastic; turgid
The word comes from the Latin grandiloquus, which combines grandis meaning "great" and loquens meaning "speaking." It originally described someone who speaks in a grand or impressive manner, similar to the related word eloquent.