Dying Town: Briefly applicable in the Empire in the time period between the Industrial Revolution and the Automation Revolution. After the former, there was flight from plenty of small towns into the cities, to concentrate labor for the needs of industry and as agricultural labor requirements went down, and because of the cities being the centers of education and culture and production, much like today.
Then the Automation Revolution (and mature information technology) came along, and this trend abruptly reversed itself, as industrial labor requirements also dropped precipitately (meaning both that the remaining types of work were much more flexible as to location, and that much smaller populations could support industry), mature infotech could bring all that education and culture to you wherever you were or take you to it via telepresence, and modern robotized delivery systems could do much the same for production – and fast automated transit could still get you into the cities for anything that you needed to be there for.
And it turns out, for the eldrae at least, if there’s not a reason to make people live all tightly packed together in huge numbers, they pretty much don’t want to. (At least not if they can still have all the good things about city delivered or a short flitter-hop away.) Former dying towns are the new suburbs.