Grandiloquent

[Merna]

gran-DIL-uh-kwuhnt, adjective:
[Lofty] [in style]; pompous; [bombastic]. Full of fine words and fancy expressions - marked by the use of impressive-sounding but mostly meaningless words and phrases.

[Becky]

using big or [important] words in [order] to [impress]

[Dorothey Allen]

Pompous or extravagant in language, style, or manner, especially in a way that is intended to impress.