Uptown | Place/slang | Uptown is drug slang for cocaine, the opposite of down (heroin). It is also a place in New York which is probably why someone thought it would be a good idea to use it in reference to Mount Pleasant, just like SoMa. We blame condos marketers.
Usage: “This drug dealer offered me some ‘uptown’ and I was all confused so I said, like, “Mount Pleasant is totally that way, dude…”