The word 'poly' in this case refers to 'polygons'. Essentially it's just a low-resolution image of something. In this case, it's an artistic expression of the ideas. This client in involved with stocks and trading and asked for a 4" tall representation of the two types of market states, a Bull Market and a Bear Market.
These two models where an interesting lesson to learn that hadn't shown up in other projects. While loosing about 32hrs worth of printing time in total, it was worth it. Each model took 27-28hrs to print.