What’s the meaning of “she has some mouth on her”?
The idiom comes from an episode (S03E03) of Seinfeld:
-He loves that pen.
-Come on.
He talks about it all the time.
He goes on and on about how it writes upside down, how astronauts use it.
He never should have offered it.
-He didn't think you'd accept.
-Well, he was wrong.
I know his wife.
She has some mouth on her. She'll tell everyone in the condo now that you made him give you the pen. They're talking about it right now.