Grandiloquence is a lofty, high-flown style of talking that has a lot of fluff but may lack substance. It’s too grand to be eloquent, so grandiloquence is usually annoying.
Grandiloquence comes from the Latin word grandis for, yes, “grand” and loqui for “speak.”Grandiloquence is also related to loquacious (talkative), soliloquy (a solo speech), and other words about talk. Grandiloquence is a type of talk that is pompous and bombastic, full of pretty-sounding words and elegant turns of phrase that add up to nothing. Politicians who say nothing but make it sound important are masters of grandiloquence.