1) a fictitious retailer that sells "jerks." 2) a line that one imagines to be the perfect comeback
1) REILLY: The ocean called. They're running outta shrimp.
GEORGE: Oh yeah, Reilly? Well, the jerkstore called. They're running outta you.
REILLY: What's the difference? You're their all-time best
2)GEORGE: Don't you understand? It's not about him. To have a line as perfect as "jerkstore" and to never use it. I, I couldn't live with myself.
ELAINE: See, there are no jerkstores. It..it's just a little confusing, is all.
GEORGE: It's smart. It's a smart line, and a smart crowd will appreciate it. And, I'm not gonna dumb it down for some bonehead mass audience!