Definition of "Manhattanite"

This does not take into account the tens of thousands of New Yorkers who are harmlessly and charmingly insane in a peculiarly Manhattanite manner.

1946, George Johnston, Skyscrapers in the Mist, page 52

The most likely explanation is that Cage imagined Peter as a fop of the first order, the type of ivory-tower Manhattanite whose exalted sense of privilege naturally leads to a hilariously affected manner of speech.

2012 May 24, Scott Tobias, “Film: Reviews: Vampire's Kiss”, in The Onion AV Club‎