Marked by or given to speech or writing that is given exaggerated importance by artificial or empty mean (as defined by Merriam-Webster)

Memorization Aid:

The president gave a bombastic speech, in which he claimed he once had a bomb thrown at him, when it fact it was just a gymnast jumping towards him.

Example Sentence:

Although the researcher’s claims seem valid and reasonable, his bombastic speech causes him to appear otherwise.