Conversation in an airport

Random discussion about me being older than dinosaurs devolved into the following:

Zach (to DJ): Yeah? Well, your mom's the big bang
Me: *raised eyebrow @ Zach*
Zach: I feel so bad
Me: No you don't. The fact you're chuckling says you don't feel bad
Zach: I'm actually chortling, not chuckling
DJ: What is a chortle
Zach: It's a type of cake
DJ: Really?

Ladies and gentleman, my pride and joy.