The phrase "roll seam" refers to a technique used in sewing or crafting where two pieces of fabric are rolled over and sewn together to create a neat and secure edge or seam. Full definition
Now spray or butter a loaf pan and place the bread roll seam side down into the pan, pressing the dough gently into the sides of the pan. (flavorquotient.com)
Place the cabbage roll seam side down in the casserole dish. (staceyhomemaker.com)
Place the completed rolls seam side down on the prepared baking sheet. (emilybites.com)