noun
bombast
BAHM-bast/ˈbɑːmbæst/
Speech or writing that sounds grand but has little substance.
The speech offers plenty of bombast but almost no practical detail.

Etymology
Cotton used as stuffing or padding supplied the image behind bombast. Language that swells with grand expressions but adds little substance is figuratively padded out.
In context
… mere bombast fraud deception impiety and hypocrisy a thin wall to cover up crimes …
More examples
- She cut the bombast from the draft.
- His grand promises sounded like empty bombast.
- The critic disliked the novel's political bombast.
Similar words
- grandiloquence
- An elevated style that need not be wholly empty.
- bluster
- Loud or threatening talk rather than elaborate rhetorical inflation.