Tyler was downstairs, watching Balto III. She came racing upstairs, and breathlessly asked "Dad, what's chemistry?"

I drew a deep breath, and quickly assembled what I thought was an adequate way to explain the science of chemistry. "Chemistry is science with chemicals. Scientists mix chemicals, and make experi-"

"'You and me have chemistry'" Tyler interrupted, quoting the movie downstairs with a questioning look in her eye.

"Oh. That's an expression that means someone thinks they'd be a good boyfriend and girlfriend."

Tyler raced back downstairs, happy to learn the meaning of this new idiom.