The term "artist's brown" refers to a specific shade of brown that is commonly used by artists. However, there are several synonyms that can be used in place of this term, depending on the specific shade intended. For example, sienna is a reddish-brown shade that is similar to artist's brown. Burnt umber is a warm, dark brown shade that can also be used interchangeably. Raw umber is a lighter, cooler brown that can be used to achieve a different effect. Other options include ochre, sepia, and chestnut. Ultimately, the choice of synonym will depend on the artist's personal preference and the desired outcome of the artwork.