Magniloquent

The magniloquent politician promised to solve all the country's problems if elected, but failed to deliver.

The magniloquent neighbor bragged about his expensive car.

The magniloquent doctor claimed to have a cure for a disease that had no known cure.

The lawyer's magniloquent arguments failed to sway the judge.

The magniloquent salesman promised us the world, but couldn't deliver.

The writer's magniloquent prose was praised by some, but criticized by others as being pretentious.

His magniloquent speech made it hard for anyone to understand his point.