A neighborhood within a neighborhood. And happens to be one of the most charming nabes in all New York. "Hudson Heights" as a name has only been used in the gentrification sense since the 90'd. But the actual area has always been nice, coming from a lifelong resident. Located in Washington Heights, Hudson Heights comprises anything from 181 St and Ft Washington Ave to Fort Tryon Park and west of Broadway up until 190St.
Long a haven for German Jews, it was nicknamed "Frankfurt on the Hudson" during the WW II years. today, most of the original German Jews have dies or retired, and it has found insured life with new, hipsterfied residents. While not a Williamsburg by any measure, the newer residents are young, artsy and many of them are non New Yorkers.
The area is known, in particular, for its natural beauty. Fort Tryon Park is one of the most tranquil anywhere. The playground i grew up in, Bennett Park, is at the highest natural point on Manhattan island. Bennett Park is located at 184 St between Ft Washington and Pinehurst Avenues. When it comes to living, it is a quality place to live, all while still being a part of Manhattan island.
Hudson Heights is a real estate term to differentiate it from the rest of Washington Heights.