bloviate \BLOH-vee-ayt\ verb:
To speak or write at length in a pompous or boastful manner.
Example:
After five years as president and thirty years as a political figure, this colossal oaf is still unable to discipline his urge to … bloviate. — R. Emmett Tyrrell Jr., American Spectator, December 19, 1997
Origin: Bloviate is from blow + a mock-Latinate suffix -viate. Compare blowhard, “a boaster or braggart.” Bloviation is the noun form; a bloviator is one who bloviates.