The funny thing is that "Cass Corridor" was originally a planning term too. It goes back to the great city planning/urban renewal era that ran from the late '40s to the early '60s. Specifically, it has to do with what was discussed in the thread linked by MSUguy earlier here [[Dookie Joe particularly discusses it there): the planned relocation of 'less desirable' populations, like Chinese people or the residents of the old Skid Row on Michigan Ave., to the area just west of Woodward.

Quote Originally Posted by Hermod View Post
Back in the 40s and 50s, you would rarely hear areas called by a name [[Brightmore, East English Village, West Village). Areas were referred to by the major cross streets [[I live near Harper & Chalmers). "Downtown" was a vague thing meaning "down by Hudsons".
This is quite true. Other than very well-defined areas like Indian Village or Palmer Woods, most Detroit neighborhoods were largely undifferentiated and usually simply referred to by nearby major streets until the rise of urban planning. My Dad, who has spent his entire nearly 90 years in the city, still does that.

"Cass Corridor" was an urban panning attempt to define an area west of Woodward, north of downtown, and south of the university, that had certain characteristics [[a high-density collection of apartment dwellings, a mostly white working class-to-poor population with a higher than normal number of transients, and several high traffic north-south "corridor" streets with transit connections) by naming it after a very recognizable street. The name stuck with everybody because of those connections, and because it came to recognizably describe, in an easy short-hand, the unique mix that resulted from a mix of normal population shifts and the dynamics set in motion by urban planning decisions.