The word many non-Chicagoans use to describe Chicago, but end up sounding lame because most Chicagoans think they're talking about China Town. Similar to how non-Chicagoans use the term "Willis Tower," but get nothing from that because Chicagoans never use that term unless they work there. (Real life experience.)
Girl: Wanna go to Chi Town with me?
Boy: Uh, sorry, I'm allergic to Chinese food.
Girl: I mean Chicago!
Boy: Is that what they call us? The world is ending!