talk through one's hat
- (idiomatic) To speak lacking expertise, authority, or knowledge; to invent or fabricate facts.
- (idiomatic) To assert something as true or valid; to bluff.
1922, P. G. Wodehouse, chapter 14, in Right Ho, Jeeves:
- He's conceited and opinionative and argues all the time, even when he knows perfectly well that he's talking through his hat.
to speak lacking knowledge
- The translations below need to be checked and inserted above into the appropriate translation tables, removing any numbers. Numbers do not necessarily match those in definitions. See instructions at Wiktionary:Entry layout#Translations.