Lu: "Sometimes Ms. Brunello tells me, Lucy, you are skating on thin ice with me.' And I know what that means!" Dad: "What?"
Lu: "It is an idiom that mean she had had it up to here with me and I am about to get a consequence."
Dad: "That's exactly what that means. What are you doing when she does that?"
As Lu is describing falling out of her chair for laughs, Jason stifles laughter and proudly mouths, "IDIOM?!"