A cookie sheet is a flat baking tray used for baking sweet and savory treats. If you are looking for some synonyms for the word cookie sheet, there are a few options. One such term is a baking sheet. A baking sheet can be used for a variety of recipes beyond baked goods, including roasting vegetables or cooking proteins. Another term is a jelly roll pan. This type of pan typically has raised edges to keep batter or liquid from spilling over. A third option could be a flat baking pan. This term is suitable for thinner cookies and recipes that do not require deep sides.