You know, those words that are kind of stupid and make absolutely no sense 100 miles out of town, but everyone uses them and everyone loves them.
Being from Philadelphia, the two biggest examples I can think of are "jawn" and "bocky."
Jawn (n): an object or thing. She just picked up that jawn over there.
Bocky (n): a blow job. Pretty self explanatory. This one might have actually been specific to my high school. Our robotics team once requested one over the loudspeaker at a competition by pretending it was a spare part. "Team 423 is in need of a bocky" indeed.
For non-Philadelphians, apparently in Wisconsin they call water fountains "bubblers?" At least that's what one of my cousins from Milwaukee says. And of course, there is always the Great American Soda/Pop Debate. Don't even get me started on the "cola" people.