talk through one’s hat

talk through (one's) hat

1. To say foolish things; to talk nonsense. Don't pay Jonathan any mind, Mary, he's just talking through his hat again.
2. To exaggerate one's achievements or knowledge; to bluff or boast. Dorothy keeps saying she can outrun anyone in our school, but she's talking through her hat if you ask me. It seemed like the candidate was talking through his hat for a while when the debate turned to the topic of tax policy.
See also: hat, talk, through
Farlex Dictionary of Idioms.

talk through one’s hat

in. to say baseless things; to speak carelessly and tell lies. You don’t know what you are talking about. You’re just talking through your hat.
See also: hat, talk, through
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • talk through (one's) hat
  • talk through hat
  • talk through one's hat
  • talk through your hat
  • talk out of (one's) hat
  • talk rot
  • talk through one's hat, to
  • talk out of the back of (one's) head