Jawn is a Philadelphia noun that can stand in for the name of a person, place, or thing when the surrounding conversation makes the meaning clear.[1]
Usage
“Grab that jawn by the door” works as long as the two of you agree which thing by the door counts. Otherwise, you are bringing back a lamp.
Origin
The term is associated with Black Philadelphia speech. A connection to the word joint has been proposed, although its origin remains uncertain.