Grocery bag paper is a commonly used term to describe the material from which grocery bags are made. However, there are a few synonyms that can be used to refer to this type of paper, including kraft paper, brown paper, and sack paper. Kraft paper is a type of strong, unbleached paper that is commonly used for packaging and wrapping. Brown paper, as the name suggests, refers to paper that is brown in color and is often used for bags and packaging. Sack paper is a tough, unbleached paper that is typically used for heavy-duty industrial packaging. All of these synonyms are suitable for referencing the type of paper that grocery bags are made from.