bombast vs hot air

bombast

noun
  • High-sounding words; language above the dignity of the occasion; a pompous or ostentatious manner of writing or speaking. 

adj
  • Big without meaning, or high-sounding; bombastic, inflated; magniloquent. 

verb
  • To use high-sounding words; to speak or write in a pompous or ostentatious manner. 

  • To swell or fill out; to inflate, to pad. 

hot air

noun
  • Empty, confused, or exaggerated talk lacking meaning or substance; bluster. 

  • Air that has been heated, especially so as to function as the lifting agent of a hot-air balloon. 

How often have the words bombast and hot air occurred in a corpus of books? (source: Google Ngram Viewer )