A neighborhood is a fluid concept that is not necessarily neatly defined. When looking for information on a neighborhood, keep in mind the various ways of subdividing the geography of a city:
Census tracts are "relatively permanent statistical subdivisions of a county…population size between 1,200 and 8,000 people, with an optimum size of 4,000 people":
Block groups are “generally defined to contain between 600 and 3,000 people”:
Census blocks are the smallest census geographies. In some cases, they have no population at all: