A person hailing from the corn belt, ie Iowa, Indiana, Kansas, Nebraska, Missouri, or Illinois.
Not quite southern white trash, not quite not white trash.
Some movie theaters allow one free refill on large popcorn. By fishing a bag out of the trash, you can get some for free (they give you a new bag that says "refill"). Popcorn acquired in this fashion is called trash corn.
Before the movie, me and Bob looked through several trash canstrying to find a bag so we could get trash corn. Alas, the garbage had just been taken out.