Long words

When I was putting the boys to bed last night, Jordan and I had the following conversation:

Jordan: Mommy what is that word we were talking about, that long word, when something makes a sound and you just write the word that sounds like the sound that it made?
Rachel: Onomatopoeia?
Jordan: Right! Onomatopoeia. Today in class I got that mixed up with metamorphosis.
Rachel: You were talking about metamorphosis?
Jordan: Yes. Mrs. Murphy asked if anyone knew what metamorphosis means and I was the last one to raise my hand and no one else knew and I said the other thing. The onomatopoeia.
Rachel: Metamorphosis, wow. That means a big change.
Jordan: Yes and there is another word that starts with M, that starts with meta, another long word. I can't remember the whole word but it means thinking about thinking.
Rachel: Metacognition?
Jordan: Right, metacognition. That means when you are thinking so hard that you are even thinking about your thinking.

He intends to tell Mrs. Murphy today that when she asked about metamorphosis, he was thinking of onomatopoeia. I would think a kindergarten teacher would be uniquely entertained by that.