I use a trick I learned from my math advisor. I just say "I'm sorry, I'm kind of stupid, what does it mean? Like, what does it do?". Sometimes they will overcorrect and REALLY dumb it down, but if you can show a higher level insight, they usually pick up on it and adjust. You can direct the conversation away from abstractions and specific details and more towards first principles.

Plus... intellectuals often like to feel smart, so you have an opportunity to pump their ego a bit :)