The phrase "placed side" refers to something that is put or positioned next to something else. Think of it as two objects or things being arranged next to each other. Full definition
Dogs seem to show a preference to it as when placed side by side other formulas, it usually attract first attention in most dogs. (usbones.com)
If you roll the dough between wax paper, remove one piece of wax paper and carefully place that side of the dough into the pie pan. (glutenfreeandmore.com)