the funniest compound word ever

Today. Caleb accidentally made me laugh. Really. Really. Really. Hard.

today we were eating pineapple.
and as a result, an interesting conversation ensued:

Christian: "How do you spell pineapple?"
Mommy: "P.I.N.E.A.P.P.L.E"

Caleb: "Hey...! That's a compound word!"
Mommy: "Yes it is! Pine and Apple!"

Caleb was excused from the table.
He headed over to a pile of library books on the moon, sun, and solar system (our upcoming studies).

Caleb: "Look Mommy! A compound word! {pointing to the title of his book:} The. Moon. !!!"
Mommy: "No, Caleb. 'The' and 'Moon' are two different words that are separate. Compound words are two different words that are written together. Here. Let me find an example in your book and show you."

so. I poured through the books quickly, but no compound word turned up.

I picked up the Solar System book, and Caleb was excited. He is digging planets these days. He spotted Saturn immediately.

Caleb: "Mommy!! Is Saturn a compound word??"
Mommy: "No..."

Caleb: "Oh! Is Uranus a compound word??"

long. long. pause by mommy.
then. I laughed for about 20 minutes.

and I was the only one laughing.