Sable's hair pencil refers to a type of paintbrush made using the fur of a sable, a type of weasel. However, due to animal rights concerns, many artists prefer to use synthetic brushes instead. Synonyms for sable's hair pencil include paintbrush, artist brush, watercolor brush, oil brush, and acrylic brush. It is important to note that the quality of the brush can vary depending on the materials used in its construction. Some brushes may be better suited for certain types of paint, such as watercolors or oils, while others may be more versatile. Ultimately, the choice of brush depends on personal preference and artistic technique.