A question you ask someone to determine if "Jawn" is a part of their regular vocabulary, and thus whether they speak in an Eastern Pennsylvanian dialect. Jawn is a slang pronoun that originated in Philly. It can be used to refer to any person, place, or thing.
Billy: "Do you speak Jawn?"
Bob: "What the fuck is a John?"
Billy: "Clearly you don't. I guess you're not from Philly."
Bob: "What the fuck is a John?"
Billy: "Clearly you don't. I guess you're not from Philly."
by kgm/s July 1, 2021