"to talk through your hat"
to talk as if you know a subject thoroughly when you really don't know what you are talking about
Related words and phrases:
Two friends are chatting as they watch a political debate...
Friend 1: Do you really think this candidate knows what she's talking about.
Friend 2: Absolutely not. She's talking through her hat.
Two coworkers are talking about a recent regional meeting...
Coworker 1: Did you hear what the boss was saying at the meeting?
Coworker 2: I couldn't believe it. The boss seemed to be really intent on impressing the vice-president.
Coworker 1: What about all those ideas the boss talked about? Where did the information come from?
Coworker 2: I think the boss was completely unprepared but wanted to impress his boss.
Coworker 1: That's why he was talking through his hat.
Talking through one's hat can be a good way to lose another person's respect.
1) I talk through my hat when displaying a lack of knowledge would be detrimental to success.
2) Is he talking through his hat?
3) We have talked through our hats when necessary.
4) They have been talking through their hats since the meeting began.
5) You (all) did not talk through your hats yesterday.
6) She was talking through her hat all the way through the debate.
7) Had she talked through her hat to the point where no one believed anything that was said?
8) Had you been talking through your hat for an hour by the time anyone noticed?
9) She will talk through her hat if an unknown subject is raised.
10) Will you be talking through your hat during the entire debate?
11) He is going to have talked through his hat at least once by the time the debate concludes.
12) Will we have been talking through our hats for hours by the time the debate is over?