It's a mystery how the word seedy came to mean darkly rundown, slummy, and seamy, but it probably came from the appearance of flowers after they've shed their seeds. That's when they start to lose their color and eventually die. You'll find seedy used to describe places like dive bars, brothels, and those sections of town where dealers ply their drugs. Certain writers, such as Dennis Cooper and even Charles Dickens, are fascinated by the seedy underbelly of life in big cities, in scenes populated by wretched people and other outcasts.